diff --git a/idea/resources/META-INF/jvm.xml b/idea/resources/META-INF/jvm.xml
index 99a974c682f..5005ee32789 100644
--- a/idea/resources/META-INF/jvm.xml
+++ b/idea/resources/META-INF/jvm.xml
@@ -183,7 +183,7 @@
 
       <registryKey key="kotlin.uast.force.uinjectionhost"
                    description="Whether to convert `KtStringTemplateExpression` to `KotlinStringTemplateUPolyadicExpression` in all cases"
-                   defaultValue="false"
+                   defaultValue="true"
                    restartRequired="false"/>
 
       <registryKey key="kotlin.jps.instrument.bytecode"
diff --git a/plugins/uast-kotlin/src/org/jetbrains/uast/kotlin/KotlinUastLanguagePlugin.kt b/plugins/uast-kotlin/src/org/jetbrains/uast/kotlin/KotlinUastLanguagePlugin.kt
index 96f3dba346c..b61aa84bb18 100644
--- a/plugins/uast-kotlin/src/org/jetbrains/uast/kotlin/KotlinUastLanguagePlugin.kt
+++ b/plugins/uast-kotlin/src/org/jetbrains/uast/kotlin/KotlinUastLanguagePlugin.kt
@@ -301,7 +301,7 @@ internal object KotlinConverter {
         }
     }
 
-    var forceUInjectionHost = Registry.`is`("kotlin.uast.force.uinjectionhost", false)
+    var forceUInjectionHost = Registry.`is`("kotlin.uast.force.uinjectionhost", true)
         @TestOnly
         set(value) {
             field = value
diff --git a/plugins/uast-kotlin/testData/AnnotationComplex.log.txt b/plugins/uast-kotlin/testData/AnnotationComplex.log.txt
index 75c68f444ed..85dcbc0b8e3 100644
--- a/plugins/uast-kotlin/testData/AnnotationComplex.log.txt
+++ b/plugins/uast-kotlin/testData/AnnotationComplex.log.txt
@@ -19,8 +19,10 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='constructor_call'), argCount = 2))
                     UIdentifier (Identifier (Annotation))
                     USimpleNameReferenceExpression (identifier = <init>, resolvesTo = Annotation)
-                    ULiteralExpression (value = "sv1")
-                    ULiteralExpression (value = "sv2")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "sv1")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "sv2")
         UMethod (name = B2)
     UClass (name = AnnotationArray)
         UAnnotationMethod (name = value)
@@ -33,8 +35,10 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='array_initializer'), argCount = 2))
                         UIdentifier (Identifier (arrayOf))
                         USimpleNameReferenceExpression (identifier = arrayOf, resolvesTo = null)
-                        ULiteralExpression (value = "sar1")
-                        ULiteralExpression (value = "sar2")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "sar1")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "sar2")
         UMethod (name = C)
     UClass (name = C2)
         UAnnotation (fqName = AnnotationArray)
@@ -44,6 +48,8 @@ UFile (package = )
                     USimpleNameReferenceExpression (identifier = <init>, resolvesTo = Annotation)
                     UCallExpression (kind = UastCallKind(name='array_initializer'), argCount = 2))
                         UIdentifier (Identifier ([))
-                        ULiteralExpression (value = "[sar]1")
-                        ULiteralExpression (value = "[sar]2")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "[sar]1")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "[sar]2")
         UMethod (name = C2)
diff --git a/plugins/uast-kotlin/testData/AnnotationParameters.log.txt b/plugins/uast-kotlin/testData/AnnotationParameters.log.txt
index fe14237f6a7..2493c83b6d1 100644
--- a/plugins/uast-kotlin/testData/AnnotationParameters.log.txt
+++ b/plugins/uast-kotlin/testData/AnnotationParameters.log.txt
@@ -17,7 +17,8 @@ UFile (package = )
             UAnnotation (fqName = WithDefaultValue)
             UAnnotation (fqName = SuppressLint)
                 UNamedExpression (name = value)
-                    ULiteralExpression (value = "Lorem")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "Lorem")
             UBlockExpression
                 UReturnExpression
                     ULiteralExpression (value = 5)
@@ -30,9 +31,12 @@ UFile (package = )
             UAnnotation (fqName = SuppressLint)
                 UNamedExpression (name = value)
                     UCallExpression (kind = UastCallKind(name='array_initializer'), argCount = 3))
-                        ULiteralExpression (value = "Lorem")
-                        ULiteralExpression (value = "Ipsum")
-                        ULiteralExpression (value = "Dolor")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "Lorem")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "Ipsum")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "Dolor")
             UBlockExpression
                 UReturnExpression
                     USimpleNameReferenceExpression (identifier = Unit)
@@ -52,9 +56,12 @@ UFile (package = )
                 UNamedExpression (name = strs)
                     UCallExpression (kind = UastCallKind(name='array_initializer'), argCount = 3))
                         UIdentifier (Identifier ([))
-                        ULiteralExpression (value = "a")
-                        ULiteralExpression (value = "b")
-                        ULiteralExpression (value = "c")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "a")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "b")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "c")
             UBlockExpression
                 UReturnExpression
                     ULiteralExpression (value = 3)
diff --git a/plugins/uast-kotlin/testData/Assertion.values.txt b/plugins/uast-kotlin/testData/Assertion.values.txt
index db956afc60a..0e5aac01119 100644
--- a/plugins/uast-kotlin/testData/Assertion.values.txt
+++ b/plugins/uast-kotlin/testData/Assertion.values.txt
@@ -4,7 +4,8 @@ UFile (package = ) [public final class AssertionKt {...]
             UBlockExpression [{...}] = Nothing
                 UDeclarationsExpression [var s: java.lang.String = "Not Null"] = Undetermined
                     ULocalVariable (name = s) [var s: java.lang.String = "Not Null"]
-                        ULiteralExpression (value = "Not Null") ["Not Null"] = "Not Null"
+                        UPolyadicExpression (operator = +) ["Not Null"] = "Not Null"
+                            ULiteralExpression (value = "Not Null") ["Not Null"] = "Not Null"
                 UReturnExpression [return s!!] = Nothing
                     UPostfixExpression (operator = !!) [s!!] = (var s = "Not Null")
                         USimpleNameReferenceExpression (identifier = s) [s] = (var s = "Not Null")
diff --git a/plugins/uast-kotlin/testData/ClassAnnotation.altlog.txt b/plugins/uast-kotlin/testData/ClassAnnotation.altlog.txt
index 5153489ad5d..7c48bbb3827 100644
--- a/plugins/uast-kotlin/testData/ClassAnnotation.altlog.txt
+++ b/plugins/uast-kotlin/testData/ClassAnnotation.altlog.txt
@@ -21,7 +21,7 @@
                 [1]:[UTypeReferenceExpression (name = MyAnnotation)]
                     [1]:[USimpleNameReferenceExpression (identifier = MyAnnotation)]
                         [1]:[UIdentifier (Identifier (MyAnnotation))]
-            [1]:[ULiteralExpression (value = "class")]
+            [1]:[UPolyadicExpression (operator = +)]
                 [1]:[ULiteralExpression (value = "class")]
         [1]:[UIdentifier (Identifier (B))]
         [1]:[UExpressionList (class_body)]
@@ -31,7 +31,7 @@
                         [1]:[UTypeReferenceExpression (name = MyAnnotation)]
                             [1]:[USimpleNameReferenceExpression (identifier = MyAnnotation)]
                                 [1]:[UIdentifier (Identifier (MyAnnotation))]
-                    [1]:[ULiteralExpression (value = "inB class")]
+                    [1]:[UPolyadicExpression (operator = +)]
                         [1]:[ULiteralExpression (value = "inB class")]
                 [1]:[UIdentifier (Identifier (InB))]
                 [1]:[UExpressionList (class_body)]
@@ -41,7 +41,7 @@
                         [1]:[UTypeReferenceExpression (name = MyAnnotation)]
                             [1]:[USimpleNameReferenceExpression (identifier = MyAnnotation)]
                                 [1]:[UIdentifier (Identifier (MyAnnotation))]
-                    [1]:[ULiteralExpression (value = "companion")]
+                    [1]:[UPolyadicExpression (operator = +)]
                         [1]:[ULiteralExpression (value = "companion")]
                 [1]:[UIdentifier (Identifier (object))]
                 [1]:[UExpressionList (class_body)]
@@ -51,6 +51,6 @@
                 [1]:[UTypeReferenceExpression (name = MyAnnotation)]
                     [1]:[USimpleNameReferenceExpression (identifier = MyAnnotation)]
                         [1]:[UIdentifier (Identifier (MyAnnotation))]
-            [1]:[ULiteralExpression (value = "object")]
+            [1]:[UPolyadicExpression (operator = +)]
                 [1]:[ULiteralExpression (value = "object")]
         [1]:[UIdentifier (Identifier (Obj))]
diff --git a/plugins/uast-kotlin/testData/ClassAnnotation.log.txt b/plugins/uast-kotlin/testData/ClassAnnotation.log.txt
index fce8469ccd1..045ca3e82d7 100644
--- a/plugins/uast-kotlin/testData/ClassAnnotation.log.txt
+++ b/plugins/uast-kotlin/testData/ClassAnnotation.log.txt
@@ -7,24 +7,28 @@ UFile (package = )
     UClass (name = B)
         UAnnotation (fqName = MyAnnotation)
             UNamedExpression (name = text)
-                ULiteralExpression (value = "class")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "class")
         UField (name = Companion)
             UAnnotation (fqName = null)
         UMethod (name = B)
         UClass (name = InB)
             UAnnotation (fqName = MyAnnotation)
                 UNamedExpression (name = text)
-                    ULiteralExpression (value = "inB class")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "inB class")
             UMethod (name = InB)
         UClass (name = Companion)
             UAnnotation (fqName = MyAnnotation)
                 UNamedExpression (name = text)
-                    ULiteralExpression (value = "companion")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "companion")
             UMethod (name = Companion)
     UClass (name = Obj)
         UAnnotation (fqName = MyAnnotation)
             UNamedExpression (name = text)
-                ULiteralExpression (value = "object")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "object")
         UField (name = INSTANCE)
             UAnnotation (fqName = null)
         UMethod (name = Obj)
diff --git a/plugins/uast-kotlin/testData/ConstructorDelegate.log-ide.txt b/plugins/uast-kotlin/testData/ConstructorDelegate.log-ide.txt
index 2d91310ba21..d710b60f30f 100644
--- a/plugins/uast-kotlin/testData/ConstructorDelegate.log-ide.txt
+++ b/plugins/uast-kotlin/testData/ConstructorDelegate.log-ide.txt
@@ -33,7 +33,8 @@ UFile (package = )
                 ULiteralExpression (value = 10)
         UExpressionList (super_delegation)
             UTypeReferenceExpression (name = java.lang.CharSequence)
-            ULiteralExpression (value = "abc")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "abc")
         UMethod (name = Derived)
             UParameter (name = b)
                 UAnnotation (fqName = org.jetbrains.annotations.NotNull)
diff --git a/plugins/uast-kotlin/testData/ConstructorDelegate.log.txt b/plugins/uast-kotlin/testData/ConstructorDelegate.log.txt
index 8bf1fc9d014..c52ff446a8e 100644
--- a/plugins/uast-kotlin/testData/ConstructorDelegate.log.txt
+++ b/plugins/uast-kotlin/testData/ConstructorDelegate.log.txt
@@ -33,7 +33,8 @@ UFile (package = )
                 ULiteralExpression (value = 10)
         UExpressionList (super_delegation)
             UTypeReferenceExpression (name = java.lang.CharSequence)
-            ULiteralExpression (value = "abc")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "abc")
         UMethod (name = Derived)
             UParameter (name = b)
                 UAnnotation (fqName = org.jetbrains.annotations.NotNull)
diff --git a/plugins/uast-kotlin/testData/DefaultImpls.log.txt b/plugins/uast-kotlin/testData/DefaultImpls.log.txt
index 571591722f8..55b91423be2 100644
--- a/plugins/uast-kotlin/testData/DefaultImpls.log.txt
+++ b/plugins/uast-kotlin/testData/DefaultImpls.log.txt
@@ -3,6 +3,7 @@ UFile (package = )
         UMethod (name = bar)
             UBlockExpression
                 UReturnExpression
-                    ULiteralExpression (value = "Hello!")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "Hello!")
     UClass (name = Baz)
         UMethod (name = Baz)
diff --git a/plugins/uast-kotlin/testData/DeprecatedHidden.log.txt b/plugins/uast-kotlin/testData/DeprecatedHidden.log.txt
index 201285b464b..d53ee9c9825 100644
--- a/plugins/uast-kotlin/testData/DeprecatedHidden.log.txt
+++ b/plugins/uast-kotlin/testData/DeprecatedHidden.log.txt
@@ -10,5 +10,6 @@ UFile (package = test.pkg)
                         USimpleNameReferenceExpression (identifier = DeprecationLevel)
                         USimpleNameReferenceExpression (identifier = HIDDEN)
                 UNamedExpression (name = message)
-                    ULiteralExpression (value = "nothing")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "nothing")
             UBlockExpression
diff --git a/plugins/uast-kotlin/testData/DestructuringDeclaration.log.txt b/plugins/uast-kotlin/testData/DestructuringDeclaration.log.txt
index 288d88dd8e1..a9ae113df8c 100644
--- a/plugins/uast-kotlin/testData/DestructuringDeclaration.log.txt
+++ b/plugins/uast-kotlin/testData/DestructuringDeclaration.log.txt
@@ -8,7 +8,8 @@ UFile (package = )
                     ULocalVariable (name = var268d41a5)
                         UAnnotation (fqName = null)
                         UBinaryExpression (operator = <other>)
-                            ULiteralExpression (value = "foo")
+                            UPolyadicExpression (operator = +)
+                                ULiteralExpression (value = "foo")
                             ULiteralExpression (value = 1)
                     ULocalVariable (name = a)
                         UAnnotation (fqName = null)
@@ -29,7 +30,8 @@ UFile (package = )
                         UAnnotation (fqName = null)
                         UAnnotation (fqName = kotlin.Suppress)
                             UNamedExpression (name = names)
-                                ULiteralExpression (value = "UNCHECKED_CAST")
+                                UPolyadicExpression (operator = +)
+                                    ULiteralExpression (value = "UNCHECKED_CAST")
                         UBinaryExpressionWithType
                             USimpleNameReferenceExpression (identifier = data)
                             UTypeReferenceExpression (name = kotlin.Pair<? extends java.lang.String,? extends java.lang.String>)
diff --git a/plugins/uast-kotlin/testData/Elvis.log.txt b/plugins/uast-kotlin/testData/Elvis.log.txt
index ed8d2b3f964..98996672068 100644
--- a/plugins/uast-kotlin/testData/Elvis.log.txt
+++ b/plugins/uast-kotlin/testData/Elvis.log.txt
@@ -24,7 +24,8 @@ UFile (package = )
                                             UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                                                 UIdentifier (Identifier (foo))
                                                 USimpleNameReferenceExpression (identifier = foo, resolvesTo = null)
-                                                ULiteralExpression (value = "Lorem ipsum")
+                                                UPolyadicExpression (operator = +)
+                                                    ULiteralExpression (value = "Lorem ipsum")
                                     UIfExpression
                                         UBinaryExpression (operator = !=)
                                             USimpleNameReferenceExpression (identifier = varc4aef569)
@@ -33,7 +34,8 @@ UFile (package = )
                                         UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                                             UIdentifier (Identifier (foo))
                                             USimpleNameReferenceExpression (identifier = foo, resolvesTo = null)
-                                            ULiteralExpression (value = "dolor sit amet")
+                                            UPolyadicExpression (operator = +)
+                                                ULiteralExpression (value = "dolor sit amet")
                         UIfExpression
                             UBinaryExpression (operator = !=)
                                 USimpleNameReferenceExpression (identifier = var243c51a0)
diff --git a/plugins/uast-kotlin/testData/EnumValueMembers.log-ide.txt b/plugins/uast-kotlin/testData/EnumValueMembers.log-ide.txt
index bd07a46ab5d..03dcfa075fa 100644
--- a/plugins/uast-kotlin/testData/EnumValueMembers.log-ide.txt
+++ b/plugins/uast-kotlin/testData/EnumValueMembers.log-ide.txt
@@ -5,12 +5,14 @@ UFile (package = )
         UEnumConstant (name = SHEET)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
-            ULiteralExpression (value = "foo")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "foo")
             UClass (name = SHEET)
                 UMethod (name = getExitAnimation)
                     UBlockExpression
                         UReturnExpression
-                            ULiteralExpression (value = "bar")
+                            UPolyadicExpression (operator = +)
+                                ULiteralExpression (value = "bar")
                 UMethod (name = SHEET)
         UMethod (name = getExitAnimation)
         UMethod (name = getValue)
diff --git a/plugins/uast-kotlin/testData/EnumValueMembers.log.txt b/plugins/uast-kotlin/testData/EnumValueMembers.log.txt
index 5c76f6d87a9..70a629a4251 100644
--- a/plugins/uast-kotlin/testData/EnumValueMembers.log.txt
+++ b/plugins/uast-kotlin/testData/EnumValueMembers.log.txt
@@ -3,12 +3,14 @@ UFile (package = )
         UEnumConstant (name = SHEET)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
-            ULiteralExpression (value = "foo")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "foo")
             UClass (name = null)
                 UMethod (name = getExitAnimation)
                     UBlockExpression
                         UReturnExpression
-                            ULiteralExpression (value = "bar")
+                            UPolyadicExpression (operator = +)
+                                ULiteralExpression (value = "bar")
                 UMethod (name = SHEET)
         UField (name = value)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
diff --git a/plugins/uast-kotlin/testData/EnumValuesConstructors.log-ide.txt b/plugins/uast-kotlin/testData/EnumValuesConstructors.log-ide.txt
index 130f197f532..40dcfc29152 100644
--- a/plugins/uast-kotlin/testData/EnumValuesConstructors.log-ide.txt
+++ b/plugins/uast-kotlin/testData/EnumValuesConstructors.log-ide.txt
@@ -5,15 +5,18 @@ UFile (package = )
         UEnumConstant (name = SYSTEM)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
-            ULiteralExpression (value = "system")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "system")
         UEnumConstant (name = USER)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
-            ULiteralExpression (value = "user")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "user")
         UEnumConstant (name = INTERNAL)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
-            ULiteralExpression (value = "internal")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "internal")
         UEnumConstant (name = UNKNOWN)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
diff --git a/plugins/uast-kotlin/testData/EnumValuesConstructors.log.txt b/plugins/uast-kotlin/testData/EnumValuesConstructors.log.txt
index 71229cd080b..15e48087df0 100644
--- a/plugins/uast-kotlin/testData/EnumValuesConstructors.log.txt
+++ b/plugins/uast-kotlin/testData/EnumValuesConstructors.log.txt
@@ -3,15 +3,18 @@ UFile (package = )
         UEnumConstant (name = SYSTEM)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
-            ULiteralExpression (value = "system")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "system")
         UEnumConstant (name = USER)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
-            ULiteralExpression (value = "user")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "user")
         UEnumConstant (name = INTERNAL)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
-            ULiteralExpression (value = "internal")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "internal")
         UEnumConstant (name = UNKNOWN)
             UAnnotation (fqName = null)
             USimpleNameReferenceExpression (identifier = Style)
diff --git a/plugins/uast-kotlin/testData/IfStatement.log.txt b/plugins/uast-kotlin/testData/IfStatement.log.txt
index fdce860179d..c2e75ac1ed0 100644
--- a/plugins/uast-kotlin/testData/IfStatement.log.txt
+++ b/plugins/uast-kotlin/testData/IfStatement.log.txt
@@ -6,7 +6,9 @@ UFile (package = )
                     ULocalVariable (name = x)
                         UIfExpression
                             UBinaryExpression (operator = !=)
-                                ULiteralExpression (value = "abc")
-                                ULiteralExpression (value = "def")
+                                UPolyadicExpression (operator = +)
+                                    ULiteralExpression (value = "abc")
+                                UPolyadicExpression (operator = +)
+                                    ULiteralExpression (value = "def")
                             ULiteralExpression (value = 1)
                             ULiteralExpression (value = 0)
diff --git a/plugins/uast-kotlin/testData/LambdaReturn.log.txt b/plugins/uast-kotlin/testData/LambdaReturn.log.txt
index 39d0e1e7366..29accedb9c5 100644
--- a/plugins/uast-kotlin/testData/LambdaReturn.log.txt
+++ b/plugins/uast-kotlin/testData/LambdaReturn.log.txt
@@ -60,15 +60,18 @@ UFile (package = org.jetbrains.uast.kotlin)
                                         USimpleNameReferenceExpression (identifier = a)
                                         ULiteralExpression (value = 5)
                                     UReturnExpression
-                                        ULiteralExpression (value = "5")
+                                        UPolyadicExpression (operator = +)
+                                            ULiteralExpression (value = "5")
                                 UIfExpression
                                     UBinaryExpression (operator = >)
                                         USimpleNameReferenceExpression (identifier = a)
                                         ULiteralExpression (value = 0)
                                     UReturnExpression
-                                        ULiteralExpression (value = "1")
+                                        UPolyadicExpression (operator = +)
+                                            ULiteralExpression (value = "1")
                                     UReturnExpression
-                                        ULiteralExpression (value = "2")
+                                        UPolyadicExpression (operator = +)
+                                            ULiteralExpression (value = "2")
                 UDeclarationsExpression
                     ULocalVariable (name = lam5)
                         ULambdaExpression
@@ -77,7 +80,8 @@ UFile (package = org.jetbrains.uast.kotlin)
                             UBlockExpression
                                 UReturnExpression
                                     UBinaryExpression (operator = +)
-                                        ULiteralExpression (value = "a")
+                                        UPolyadicExpression (operator = +)
+                                            ULiteralExpression (value = "a")
                                         USimpleNameReferenceExpression (identifier = a)
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                     UIdentifier (Identifier (bar))
diff --git a/plugins/uast-kotlin/testData/LocalVariableWithAnnotation.log.txt b/plugins/uast-kotlin/testData/LocalVariableWithAnnotation.log.txt
index 0576c834e75..0d80a5a877c 100644
--- a/plugins/uast-kotlin/testData/LocalVariableWithAnnotation.log.txt
+++ b/plugins/uast-kotlin/testData/LocalVariableWithAnnotation.log.txt
@@ -5,5 +5,6 @@ UFile (package = )
                 UDeclarationsExpression
                     ULocalVariable (name = bar)
                         UAnnotation (fqName = TestAnnotation)
-                        ULiteralExpression (value = "lorem ipsum")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "lorem ipsum")
     UClass (name = TestAnnotation)
diff --git a/plugins/uast-kotlin/testData/ParametersDisorder.log-ide.txt b/plugins/uast-kotlin/testData/ParametersDisorder.log-ide.txt
index 41b9a91c725..c31359514ce 100644
--- a/plugins/uast-kotlin/testData/ParametersDisorder.log-ide.txt
+++ b/plugins/uast-kotlin/testData/ParametersDisorder.log-ide.txt
@@ -12,7 +12,8 @@ UFile (package = )
                 ULiteralExpression (value = 1)
             UParameter (name = d)
                 UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-                ULiteralExpression (value = "aaa")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "aaa")
             UBlockExpression
         UMethod (name = withReceiver)
             UParameter (name = $this$withReceiver)
@@ -32,9 +33,11 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                     UIdentifier (Identifier (withDefault))
                     USimpleNameReferenceExpression (identifier = withDefault, resolvesTo = null)
-                    ULiteralExpression (value = "bbb")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "bbb")
                 UQualifiedReferenceExpression
-                    ULiteralExpression (value = "abc")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "abc")
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                         UIdentifier (Identifier (withReceiver))
                         USimpleNameReferenceExpression (identifier = withReceiver, resolvesTo = null)
@@ -50,8 +53,10 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                     UIdentifier (Identifier (unresolvedMethod))
                     USimpleNameReferenceExpression (identifier = <anonymous class>, resolvesTo = null)
-                    ULiteralExpression (value = "param1")
-                    ULiteralExpression (value = "param2")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "param1")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "param2")
                 UQualifiedReferenceExpression
                     UQualifiedReferenceExpression
                         UQualifiedReferenceExpression
@@ -61,7 +66,8 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 4))
                         UIdentifier (Identifier (format))
                         USimpleNameReferenceExpression (identifier = format, resolvesTo = null)
-                        ULiteralExpression (value = "%i %i %i")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "%i %i %i")
                         ULiteralExpression (value = 1)
                         ULiteralExpression (value = 2)
                         ULiteralExpression (value = 3)
@@ -74,7 +80,8 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                         UIdentifier (Identifier (format))
                         USimpleNameReferenceExpression (identifier = format, resolvesTo = null)
-                        ULiteralExpression (value = "%i %i %i")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "%i %i %i")
                         UCallExpression (kind = UastCallKind(name='method_call'), argCount = 3))
                             UIdentifier (Identifier (arrayOf))
                             USimpleNameReferenceExpression (identifier = arrayOf, resolvesTo = null)
@@ -90,7 +97,8 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 3))
                         UIdentifier (Identifier (format))
                         USimpleNameReferenceExpression (identifier = format, resolvesTo = null)
-                        ULiteralExpression (value = "%i %i %i")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "%i %i %i")
                         UCallExpression (kind = UastCallKind(name='method_call'), argCount = 3))
                             UIdentifier (Identifier (arrayOf))
                             USimpleNameReferenceExpression (identifier = arrayOf, resolvesTo = null)
@@ -112,10 +120,11 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                         UIdentifier (Identifier (format))
                         USimpleNameReferenceExpression (identifier = format, resolvesTo = null)
-                        ULiteralExpression (value = "%i %i %i")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "%i %i %i")
                         UQualifiedReferenceExpression
                             UQualifiedReferenceExpression
-                                ULiteralExpression (value = "")
+                                UPolyadicExpression (value = "")
                                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                                     UIdentifier (Identifier (chunked))
                                     USimpleNameReferenceExpression (identifier = chunked, resolvesTo = null)
@@ -132,7 +141,8 @@ UFile (package = )
                     ULambdaExpression
                         UBlockExpression
                             UQualifiedReferenceExpression
-                                ULiteralExpression (value = "def")
+                                UPolyadicExpression (operator = +)
+                                    ULiteralExpression (value = "def")
                                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                                     UIdentifier (Identifier (with2Receivers))
                                     USimpleNameReferenceExpression (identifier = with2Receivers, resolvesTo = null)
@@ -142,7 +152,8 @@ UFile (package = )
             UBlockExpression
                 UObjectLiteralExpression
                     ULiteralExpression (value = 1)
-                    ULiteralExpression (value = "foo")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "foo")
                     UClass (name = null)
                         UMethod (name = )
     UClass (name = A)
diff --git a/plugins/uast-kotlin/testData/ParametersDisorder.log.txt b/plugins/uast-kotlin/testData/ParametersDisorder.log.txt
index e8a37796eef..890b37dc6d8 100644
--- a/plugins/uast-kotlin/testData/ParametersDisorder.log.txt
+++ b/plugins/uast-kotlin/testData/ParametersDisorder.log.txt
@@ -12,7 +12,8 @@ UFile (package = )
                 ULiteralExpression (value = 1)
             UParameter (name = d)
                 UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-                ULiteralExpression (value = "aaa")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "aaa")
             UBlockExpression
         UMethod (name = withReceiver)
             UParameter (name = $this$withReceiver)
@@ -32,9 +33,11 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                     UIdentifier (Identifier (withDefault))
                     USimpleNameReferenceExpression (identifier = withDefault, resolvesTo = null)
-                    ULiteralExpression (value = "bbb")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "bbb")
                 UQualifiedReferenceExpression
-                    ULiteralExpression (value = "abc")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "abc")
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                         UIdentifier (Identifier (withReceiver))
                         USimpleNameReferenceExpression (identifier = withReceiver, resolvesTo = null)
@@ -50,8 +53,10 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                     UIdentifier (Identifier (unresolvedMethod))
                     USimpleNameReferenceExpression (identifier = <anonymous class>, resolvesTo = null)
-                    ULiteralExpression (value = "param1")
-                    ULiteralExpression (value = "param2")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "param1")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "param2")
                 UQualifiedReferenceExpression
                     UQualifiedReferenceExpression
                         UQualifiedReferenceExpression
@@ -61,7 +66,8 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 4))
                         UIdentifier (Identifier (format))
                         USimpleNameReferenceExpression (identifier = format, resolvesTo = null)
-                        ULiteralExpression (value = "%i %i %i")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "%i %i %i")
                         ULiteralExpression (value = 1)
                         ULiteralExpression (value = 2)
                         ULiteralExpression (value = 3)
@@ -74,7 +80,8 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                         UIdentifier (Identifier (format))
                         USimpleNameReferenceExpression (identifier = format, resolvesTo = null)
-                        ULiteralExpression (value = "%i %i %i")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "%i %i %i")
                         UCallExpression (kind = UastCallKind(name='method_call'), argCount = 3))
                             UIdentifier (Identifier (arrayOf))
                             USimpleNameReferenceExpression (identifier = arrayOf, resolvesTo = null)
@@ -90,7 +97,8 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 3))
                         UIdentifier (Identifier (format))
                         USimpleNameReferenceExpression (identifier = format, resolvesTo = null)
-                        ULiteralExpression (value = "%i %i %i")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "%i %i %i")
                         UCallExpression (kind = UastCallKind(name='method_call'), argCount = 3))
                             UIdentifier (Identifier (arrayOf))
                             USimpleNameReferenceExpression (identifier = arrayOf, resolvesTo = null)
@@ -112,10 +120,11 @@ UFile (package = )
                     UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                         UIdentifier (Identifier (format))
                         USimpleNameReferenceExpression (identifier = format, resolvesTo = null)
-                        ULiteralExpression (value = "%i %i %i")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "%i %i %i")
                         UQualifiedReferenceExpression
                             UQualifiedReferenceExpression
-                                ULiteralExpression (value = "")
+                                UPolyadicExpression (value = "")
                                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                                     UIdentifier (Identifier (chunked))
                                     USimpleNameReferenceExpression (identifier = chunked, resolvesTo = null)
@@ -132,7 +141,8 @@ UFile (package = )
                     ULambdaExpression
                         UBlockExpression
                             UQualifiedReferenceExpression
-                                ULiteralExpression (value = "def")
+                                UPolyadicExpression (operator = +)
+                                    ULiteralExpression (value = "def")
                                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                                     UIdentifier (Identifier (with2Receivers))
                                     USimpleNameReferenceExpression (identifier = with2Receivers, resolvesTo = null)
@@ -142,7 +152,8 @@ UFile (package = )
             UBlockExpression
                 UObjectLiteralExpression
                     ULiteralExpression (value = 1)
-                    ULiteralExpression (value = "foo")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "foo")
                     UClass (name = null)
                         UMethod (name = ParametersDisorderKt$objectLiteral$1)
     UClass (name = A)
diff --git a/plugins/uast-kotlin/testData/PropertyDelegate.log.txt b/plugins/uast-kotlin/testData/PropertyDelegate.log.txt
index 42d7e5aa6fe..4b51c13ea04 100644
--- a/plugins/uast-kotlin/testData/PropertyDelegate.log.txt
+++ b/plugins/uast-kotlin/testData/PropertyDelegate.log.txt
@@ -8,7 +8,8 @@ UFile (package = )
                 ULambdaExpression
                     UBlockExpression
                         UReturnExpression
-                            ULiteralExpression (value = "/sdcard")
+                            UPolyadicExpression (operator = +)
+                                ULiteralExpression (value = "/sdcard")
         UField (name = annotatedDelegate$delegate)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
             UAnnotation (fqName = kotlin.Suppress)
@@ -32,5 +33,6 @@ UFile (package = )
                             ULambdaExpression
                                 UBlockExpression
                                     UReturnExpression
-                                        ULiteralExpression (value = "/sdcard")
+                                        UPolyadicExpression (operator = +)
+                                            ULiteralExpression (value = "/sdcard")
         UMethod (name = getAnnotatedDelegate)
diff --git a/plugins/uast-kotlin/testData/PropertyInitializer.log.txt b/plugins/uast-kotlin/testData/PropertyInitializer.log.txt
index 0445696ef71..6275b88baae 100644
--- a/plugins/uast-kotlin/testData/PropertyInitializer.log.txt
+++ b/plugins/uast-kotlin/testData/PropertyInitializer.log.txt
@@ -2,7 +2,8 @@ UFile (package = )
     UClass (name = TestPropertyInitializer)
         UField (name = withSetter)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-            ULiteralExpression (value = "/sdcard")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "/sdcard")
         UMethod (name = getWithSetter)
             UBlockExpression
                 UReturnExpression
diff --git a/plugins/uast-kotlin/testData/PropertyInitializerWithoutSetter.log-ide.txt b/plugins/uast-kotlin/testData/PropertyInitializerWithoutSetter.log-ide.txt
index 7eaac7d90ec..393ccf749c7 100644
--- a/plugins/uast-kotlin/testData/PropertyInitializerWithoutSetter.log-ide.txt
+++ b/plugins/uast-kotlin/testData/PropertyInitializerWithoutSetter.log-ide.txt
@@ -2,11 +2,12 @@ UFile (package = )
     UClass (name = PropertyInitializerWithoutSetterKt)
         UField (name = withoutSetter)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-            ULiteralExpression (value = "/sdcard")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "/sdcard")
         UMethod (name = getWithoutSetter)
             UBlockExpression
                 UReturnExpression
                     USimpleNameReferenceExpression (identifier = field)
         UMethod (name = setWithoutSetter)
             UParameter (name = withoutSetter)
-                UAnnotation (fqName = org.jetbrains.annotations.NotNull)
\ No newline at end of file
+                UAnnotation (fqName = org.jetbrains.annotations.NotNull)
diff --git a/plugins/uast-kotlin/testData/PropertyInitializerWithoutSetter.log.txt b/plugins/uast-kotlin/testData/PropertyInitializerWithoutSetter.log.txt
index 2617618a649..ee33807a98e 100644
--- a/plugins/uast-kotlin/testData/PropertyInitializerWithoutSetter.log.txt
+++ b/plugins/uast-kotlin/testData/PropertyInitializerWithoutSetter.log.txt
@@ -2,7 +2,8 @@ UFile (package = )
     UClass (name = PropertyInitializerWithoutSetterKt)
         UField (name = withoutSetter)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-            ULiteralExpression (value = "/sdcard")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "/sdcard")
         UMethod (name = getWithoutSetter)
             UBlockExpression
                 UReturnExpression
diff --git a/plugins/uast-kotlin/testData/Simple.log.txt b/plugins/uast-kotlin/testData/Simple.log.txt
index f352eb5b902..ae1a89bc75c 100644
--- a/plugins/uast-kotlin/testData/Simple.log.txt
+++ b/plugins/uast-kotlin/testData/Simple.log.txt
@@ -2,12 +2,14 @@ UFile (package = )
     UClass (name = Simple)
         UField (name = property)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-            ULiteralExpression (value = "Mary")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "Mary")
         UMethod (name = method)
             UBlockExpression
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                     UIdentifier (Identifier (println))
                     USimpleNameReferenceExpression (identifier = println, resolvesTo = null)
-                    ULiteralExpression (value = "Hello, world!")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "Hello, world!")
         UMethod (name = getProperty)
         UMethod (name = Simple)
diff --git a/plugins/uast-kotlin/testData/Simple.values.txt b/plugins/uast-kotlin/testData/Simple.values.txt
index 24a7ff0f4aa..4c83c6a9bb6 100644
--- a/plugins/uast-kotlin/testData/Simple.values.txt
+++ b/plugins/uast-kotlin/testData/Simple.values.txt
@@ -2,12 +2,14 @@ UFile (package = ) [public final class Simple {...]
     UClass (name = Simple) [public final class Simple {...}]
         UField (name = property) [@org.jetbrains.annotations.NotNull private final var property: java.lang.String = "Mary"]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
-            ULiteralExpression (value = "Mary") ["Mary"] = "Mary"
+            UPolyadicExpression (operator = +) ["Mary"] = "Mary"
+                ULiteralExpression (value = "Mary") ["Mary"] = "Mary"
         UMethod (name = method) [public final fun method() : void {...}]
             UBlockExpression [{...}] = external println("Hello, world!")("Hello, world!")
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1)) [println("Hello, world!")] = external println("Hello, world!")("Hello, world!")
                     UIdentifier (Identifier (println)) [UIdentifier (Identifier (println))]
                     USimpleNameReferenceExpression (identifier = println, resolvesTo = null) [println] = external println("Hello, world!")("Hello, world!")
-                    ULiteralExpression (value = "Hello, world!") ["Hello, world!"] = "Hello, world!"
+                    UPolyadicExpression (operator = +) ["Hello, world!"] = "Hello, world!"
+                        ULiteralExpression (value = "Hello, world!") ["Hello, world!"] = "Hello, world!"
         UMethod (name = getProperty) [public final fun getProperty() : java.lang.String = UastEmptyExpression]
         UMethod (name = Simple) [public fun Simple() = UastEmptyExpression]
diff --git a/plugins/uast-kotlin/testData/SimpleScript.log.txt b/plugins/uast-kotlin/testData/SimpleScript.log.txt
index af6b6f03ba0..4efd0d1119e 100644
--- a/plugins/uast-kotlin/testData/SimpleScript.log.txt
+++ b/plugins/uast-kotlin/testData/SimpleScript.log.txt
@@ -22,7 +22,8 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                     UIdentifier (Identifier (println))
                     USimpleNameReferenceExpression (identifier = println, resolvesTo = null)
-                    ULiteralExpression (value = "Hello World!")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "Hello World!")
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                     UIdentifier (Identifier (getBarOrNull))
                     USimpleNameReferenceExpression (identifier = getBarOrNull, resolvesTo = null)
@@ -30,7 +31,8 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                     UIdentifier (Identifier (println))
                     USimpleNameReferenceExpression (identifier = println, resolvesTo = null)
-                    ULiteralExpression (value = "Goodbye World!")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "Goodbye World!")
         UClass (name = Bar)
             UField (name = b)
                 UAnnotation (fqName = org.jetbrains.annotations.NotNull)
diff --git a/plugins/uast-kotlin/testData/StringTemplate.log.txt b/plugins/uast-kotlin/testData/StringTemplate.log.txt
index 1f25dbd51a5..548702812cc 100644
--- a/plugins/uast-kotlin/testData/StringTemplate.log.txt
+++ b/plugins/uast-kotlin/testData/StringTemplate.log.txt
@@ -2,13 +2,16 @@ UFile (package = )
     UClass (name = StringTemplateKt)
         UField (name = foo)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-            ULiteralExpression (value = "lorem")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "lorem")
         UField (name = bar)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-            ULiteralExpression (value = "ipsum")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "ipsum")
         UField (name = baz)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-            ULiteralExpression (value = "dolor")
+            UPolyadicExpression (operator = +)
+                ULiteralExpression (value = "dolor")
         UField (name = foobarbaz)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
             UPolyadicExpression (operator = +)
diff --git a/plugins/uast-kotlin/testData/StringTemplate.types.txt b/plugins/uast-kotlin/testData/StringTemplate.types.txt
index 01a7d9cdde5..14c966253b3 100644
--- a/plugins/uast-kotlin/testData/StringTemplate.types.txt
+++ b/plugins/uast-kotlin/testData/StringTemplate.types.txt
@@ -2,13 +2,16 @@ UFile (package = ) [public final class StringTemplateKt {...]
     UClass (name = StringTemplateKt) [public final class StringTemplateKt {...}]
         UField (name = foo) [@org.jetbrains.annotations.NotNull private static final var foo: java.lang.String = "lorem"]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
-            ULiteralExpression (value = "lorem") ["lorem"] : PsiType:String
+            UPolyadicExpression (operator = +) ["lorem"] : PsiType:String
+                ULiteralExpression (value = "lorem") ["lorem"] : PsiType:String
         UField (name = bar) [@org.jetbrains.annotations.NotNull private static final var bar: java.lang.String = "ipsum"]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
-            ULiteralExpression (value = "ipsum") ["ipsum"] : PsiType:String
+            UPolyadicExpression (operator = +) ["ipsum"] : PsiType:String
+                ULiteralExpression (value = "ipsum") ["ipsum"] : PsiType:String
         UField (name = baz) [@org.jetbrains.annotations.NotNull private static final var baz: java.lang.String = "dolor"]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
-            ULiteralExpression (value = "dolor") ["dolor"] : PsiType:String
+            UPolyadicExpression (operator = +) ["dolor"] : PsiType:String
+                ULiteralExpression (value = "dolor") ["dolor"] : PsiType:String
         UField (name = foobarbaz) [@org.jetbrains.annotations.NotNull private static final var foobarbaz: java.lang.String = foo + " " + bar + " " + baz]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
             UPolyadicExpression (operator = +) [foo + " " + bar + " " + baz] : PsiType:String
diff --git a/plugins/uast-kotlin/testData/StringTemplateComplex.log.txt b/plugins/uast-kotlin/testData/StringTemplateComplex.log.txt
index 57cb9a77c1e..70bc02526cb 100644
--- a/plugins/uast-kotlin/testData/StringTemplateComplex.log.txt
+++ b/plugins/uast-kotlin/testData/StringTemplateComplex.log.txt
@@ -2,20 +2,27 @@ UFile (package = )
     UClass (name = StringTemplateComplexKt)
         UField (name = muchRecur)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
-            ULiteralExpression (value = "abc")
+            UPolyadicExpression (operator = +)
+                UPolyadicExpression (operator = +)
+                    UPolyadicExpression (operator = +)
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "abc")
         UField (name = case4)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
             UPolyadicExpression (operator = +)
                 ULiteralExpression (value = "a ")
-                ULiteralExpression (value = "literal")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "literal")
                 ULiteralExpression (value = " z")
         UField (name = case5)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
             UPolyadicExpression (operator = +)
                 ULiteralExpression (value = "a ")
-                ULiteralExpression (value = "literal")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "literal")
                 ULiteralExpression (value = " ")
-                ULiteralExpression (value = "literal")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "literal")
                 ULiteralExpression (value = " z")
         UField (name = literalInLiteral)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
@@ -49,18 +56,21 @@ UFile (package = )
                 ULiteralExpression (value = 0)
             UBlockExpression
                 UReturnExpression
-                    USimpleNameReferenceExpression (identifier = i)
+                    UPolyadicExpression (operator = +)
+                        USimpleNameReferenceExpression (identifier = i)
         UMethod (name = foo)
             UBlockExpression
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1))
                     UIdentifier (Identifier (println))
                     USimpleNameReferenceExpression (identifier = println, resolvesTo = null)
-                    USimpleNameReferenceExpression (identifier = baz)
+                    UPolyadicExpression (operator = +)
+                        USimpleNameReferenceExpression (identifier = baz)
                 UDeclarationsExpression
                     ULocalVariable (name = template1)
-                        UCallExpression (kind = UastCallKind(name='method_call'), argCount = 0))
-                            UIdentifier (Identifier (simpleForTemplate))
-                            USimpleNameReferenceExpression (identifier = simpleForTemplate, resolvesTo = null)
+                        UPolyadicExpression (operator = +)
+                            UCallExpression (kind = UastCallKind(name='method_call'), argCount = 0))
+                                UIdentifier (Identifier (simpleForTemplate))
+                                USimpleNameReferenceExpression (identifier = simpleForTemplate, resolvesTo = null)
                 UDeclarationsExpression
                     ULocalVariable (name = template2)
                         UPolyadicExpression (operator = +)
diff --git a/plugins/uast-kotlin/testData/StringTemplateComplex.types.txt b/plugins/uast-kotlin/testData/StringTemplateComplex.types.txt
index 646606ebb2e..5e1914e0d2f 100644
--- a/plugins/uast-kotlin/testData/StringTemplateComplex.types.txt
+++ b/plugins/uast-kotlin/testData/StringTemplateComplex.types.txt
@@ -2,20 +2,27 @@ UFile (package = ) [public final class StringTemplateComplexKt {...]
     UClass (name = StringTemplateComplexKt) [public final class StringTemplateComplexKt {...}]
         UField (name = muchRecur) [@org.jetbrains.annotations.NotNull private static final var muchRecur: java.lang.String = "abc"]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
-            ULiteralExpression (value = "abc") ["abc"] : PsiType:String
+            UPolyadicExpression (operator = +) ["abc"] : PsiType:String
+                UPolyadicExpression (operator = +) ["abc"] : PsiType:String
+                    UPolyadicExpression (operator = +) ["abc"] : PsiType:String
+                        UPolyadicExpression (operator = +) ["abc"] : PsiType:String
+                            ULiteralExpression (value = "abc") ["abc"] : PsiType:String
         UField (name = case4) [@org.jetbrains.annotations.NotNull private static final var case4: java.lang.String = "a " + "literal" + " z"]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
             UPolyadicExpression (operator = +) ["a " + "literal" + " z"] : PsiType:String
                 ULiteralExpression (value = "a ") ["a "] : PsiType:String
-                ULiteralExpression (value = "literal") ["literal"] : PsiType:String
+                UPolyadicExpression (operator = +) ["literal"] : PsiType:String
+                    ULiteralExpression (value = "literal") ["literal"] : PsiType:String
                 ULiteralExpression (value = " z") [" z"] : PsiType:String
         UField (name = case5) [@org.jetbrains.annotations.NotNull private static final var case5: java.lang.String = "a " + "literal" + " " + "literal" + " z"]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
             UPolyadicExpression (operator = +) ["a " + "literal" + " " + "literal" + " z"] : PsiType:String
                 ULiteralExpression (value = "a ") ["a "] : PsiType:String
-                ULiteralExpression (value = "literal") ["literal"] : PsiType:String
+                UPolyadicExpression (operator = +) ["literal"] : PsiType:String
+                    ULiteralExpression (value = "literal") ["literal"] : PsiType:String
                 ULiteralExpression (value = " ") [" "] : PsiType:String
-                ULiteralExpression (value = "literal") ["literal"] : PsiType:String
+                UPolyadicExpression (operator = +) ["literal"] : PsiType:String
+                    ULiteralExpression (value = "literal") ["literal"] : PsiType:String
                 ULiteralExpression (value = " z") [" z"] : PsiType:String
         UField (name = literalInLiteral) [@org.jetbrains.annotations.NotNull private static final var literalInLiteral: java.lang.String = "a " + "literal" + case4 + " z"]
             UAnnotation (fqName = org.jetbrains.annotations.NotNull) [@org.jetbrains.annotations.NotNull]
@@ -49,18 +56,21 @@ UFile (package = ) [public final class StringTemplateComplexKt {...]
                 ULiteralExpression (value = 0) [0] : PsiType:int
             UBlockExpression [{...}]
                 UReturnExpression [return i]
-                    USimpleNameReferenceExpression (identifier = i) [i] : PsiType:int
+                    UPolyadicExpression (operator = +) [i] : PsiType:String
+                        USimpleNameReferenceExpression (identifier = i) [i] : PsiType:int
         UMethod (name = foo) [public static final fun foo() : void {...}]
             UBlockExpression [{...}] : PsiType:void
                 UCallExpression (kind = UastCallKind(name='method_call'), argCount = 1)) [println(baz)] : PsiType:void
                     UIdentifier (Identifier (println)) [UIdentifier (Identifier (println))]
                     USimpleNameReferenceExpression (identifier = println, resolvesTo = null) [println] : PsiType:void
-                    USimpleNameReferenceExpression (identifier = baz) [baz]
+                    UPolyadicExpression (operator = +) [baz] : PsiType:String
+                        USimpleNameReferenceExpression (identifier = baz) [baz]
                 UDeclarationsExpression [var template1: java.lang.String = simpleForTemplate()]
                     ULocalVariable (name = template1) [var template1: java.lang.String = simpleForTemplate()]
-                        UCallExpression (kind = UastCallKind(name='method_call'), argCount = 0)) [simpleForTemplate()] : PsiType:String
-                            UIdentifier (Identifier (simpleForTemplate)) [UIdentifier (Identifier (simpleForTemplate))]
-                            USimpleNameReferenceExpression (identifier = simpleForTemplate, resolvesTo = null) [simpleForTemplate] : PsiType:String
+                        UPolyadicExpression (operator = +) [simpleForTemplate()] : PsiType:String
+                            UCallExpression (kind = UastCallKind(name='method_call'), argCount = 0)) [simpleForTemplate()] : PsiType:String
+                                UIdentifier (Identifier (simpleForTemplate)) [UIdentifier (Identifier (simpleForTemplate))]
+                                USimpleNameReferenceExpression (identifier = simpleForTemplate, resolvesTo = null) [simpleForTemplate] : PsiType:String
                 UDeclarationsExpression [var template2: java.lang.String = "." + simpleForTemplate()]
                     ULocalVariable (name = template2) [var template2: java.lang.String = "." + simpleForTemplate()]
                         UPolyadicExpression (operator = +) ["." + simpleForTemplate()] : PsiType:String
diff --git a/plugins/uast-kotlin/testData/SuperCalls.log-ide.txt b/plugins/uast-kotlin/testData/SuperCalls.log-ide.txt
index e55664a2f9a..3924d4b727b 100644
--- a/plugins/uast-kotlin/testData/SuperCalls.log-ide.txt
+++ b/plugins/uast-kotlin/testData/SuperCalls.log-ide.txt
@@ -3,7 +3,8 @@ UFile (package = )
         UField (name = anon)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
             UObjectLiteralExpression
-                ULiteralExpression (value = "textForAnon")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "textForAnon")
                 UClass (name = null)
                     UMethod (name = bar)
                         UBlockExpression
@@ -11,7 +12,8 @@ UFile (package = )
                                 UIdentifier (Identifier (cons))
                                 USimpleNameReferenceExpression (identifier = cons, resolvesTo = null)
                                 UObjectLiteralExpression
-                                    ULiteralExpression (value = "inner literal")
+                                    UPolyadicExpression (operator = +)
+                                        ULiteralExpression (value = "inner literal")
                                     UClass (name = null)
                                         UMethod (name = )
                     UMethod (name = )
@@ -21,7 +23,8 @@ UFile (package = )
                                 UCallExpression (kind = UastCallKind(name='constructor_call'), argCount = 1))
                                     UIdentifier (Identifier (A))
                                     USimpleNameReferenceExpression (identifier = <init>, resolvesTo = A)
-                                    ULiteralExpression (value = "inner class")
+                                    UPolyadicExpression (operator = +)
+                                        ULiteralExpression (value = "inner class")
         UMethod (name = getAnon)
         UMethod (name = cons)
             UParameter (name = a)
@@ -97,4 +100,5 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='constructor_call'), argCount = 1))
                     UIdentifier (Identifier (A))
                     USimpleNameReferenceExpression (identifier = <init>, resolvesTo = A)
-                    ULiteralExpression (value = "text")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "text")
diff --git a/plugins/uast-kotlin/testData/SuperCalls.log.txt b/plugins/uast-kotlin/testData/SuperCalls.log.txt
index 5cdd4558f78..7f449519c10 100644
--- a/plugins/uast-kotlin/testData/SuperCalls.log.txt
+++ b/plugins/uast-kotlin/testData/SuperCalls.log.txt
@@ -3,7 +3,8 @@ UFile (package = )
         UField (name = anon)
             UAnnotation (fqName = org.jetbrains.annotations.NotNull)
             UObjectLiteralExpression
-                ULiteralExpression (value = "textForAnon")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "textForAnon")
                 UClass (name = null)
                     UMethod (name = bar)
                         UBlockExpression
@@ -11,7 +12,8 @@ UFile (package = )
                                 UIdentifier (Identifier (cons))
                                 USimpleNameReferenceExpression (identifier = cons, resolvesTo = null)
                                 UObjectLiteralExpression
-                                    ULiteralExpression (value = "inner literal")
+                                    UPolyadicExpression (operator = +)
+                                        ULiteralExpression (value = "inner literal")
                                     UClass (name = null)
                                         UMethod (name = SuperCallsKt$anon$1$bar$1)
                     UMethod (name = SuperCallsKt$anon$1)
@@ -21,7 +23,8 @@ UFile (package = )
                                 UCallExpression (kind = UastCallKind(name='constructor_call'), argCount = 1))
                                     UIdentifier (Identifier (A))
                                     USimpleNameReferenceExpression (identifier = <init>, resolvesTo = A)
-                                    ULiteralExpression (value = "inner class")
+                                    UPolyadicExpression (operator = +)
+                                        ULiteralExpression (value = "inner class")
         UMethod (name = getAnon)
         UMethod (name = cons)
             UParameter (name = a)
@@ -97,4 +100,5 @@ UFile (package = )
                 UCallExpression (kind = UastCallKind(name='constructor_call'), argCount = 1))
                     UIdentifier (Identifier (A))
                     USimpleNameReferenceExpression (identifier = <init>, resolvesTo = A)
-                    ULiteralExpression (value = "text")
+                    UPolyadicExpression (operator = +)
+                        ULiteralExpression (value = "text")
diff --git a/plugins/uast-kotlin/testData/TypeReferences.log.txt b/plugins/uast-kotlin/testData/TypeReferences.log.txt
index 6173abf45b4..2fff6b7146f 100644
--- a/plugins/uast-kotlin/testData/TypeReferences.log.txt
+++ b/plugins/uast-kotlin/testData/TypeReferences.log.txt
@@ -6,10 +6,12 @@ UFile (package = )
             UBlockExpression
                 UDeclarationsExpression
                     ULocalVariable (name = varWithType)
-                        ULiteralExpression (value = "Not Null")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "Not Null")
                 UDeclarationsExpression
                     ULocalVariable (name = varWithoutType)
-                        ULiteralExpression (value = "lorem ipsum")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "lorem ipsum")
                 UDeclarationsExpression
                     ULocalVariable (name = result)
                         UBinaryExpression (operator = +)
diff --git a/plugins/uast-kotlin/testData/UnexpectedContainerException.log-ide.txt b/plugins/uast-kotlin/testData/UnexpectedContainerException.log-ide.txt
index 29df09cd201..370f70a78ff 100644
--- a/plugins/uast-kotlin/testData/UnexpectedContainerException.log-ide.txt
+++ b/plugins/uast-kotlin/testData/UnexpectedContainerException.log-ide.txt
@@ -36,5 +36,5 @@ UFile (package = )
                                                         UCallExpression (kind = UastCallKind(name='constructor_call'), argCount = 1))
                                                             UIdentifier (Identifier (UnsupportedOperationException))
                                                             USimpleNameReferenceExpression (identifier = <init>, resolvesTo = UnsupportedOperationException)
-                                                            ULiteralExpression (value = "")
+                                                            UPolyadicExpression (value = "")
                                             UMethod (name = )
diff --git a/plugins/uast-kotlin/testData/UnexpectedContainerException.log.txt b/plugins/uast-kotlin/testData/UnexpectedContainerException.log.txt
index d8b0fa29d03..57c397a0009 100644
--- a/plugins/uast-kotlin/testData/UnexpectedContainerException.log.txt
+++ b/plugins/uast-kotlin/testData/UnexpectedContainerException.log.txt
@@ -36,5 +36,5 @@ UFile (package = )
                                                         UCallExpression (kind = UastCallKind(name='constructor_call'), argCount = 1))
                                                             UIdentifier (Identifier (UnsupportedOperationException))
                                                             USimpleNameReferenceExpression (identifier = <init>, resolvesTo = UnsupportedOperationException)
-                                                            ULiteralExpression (value = "")
+                                                            UPolyadicExpression (value = "")
                                             UMethod (name = Model$1$1)
diff --git a/plugins/uast-kotlin/testData/UnexpectedContainerException.types.txt b/plugins/uast-kotlin/testData/UnexpectedContainerException.types.txt
index 9b22766399f..2e498cbe727 100644
--- a/plugins/uast-kotlin/testData/UnexpectedContainerException.types.txt
+++ b/plugins/uast-kotlin/testData/UnexpectedContainerException.types.txt
@@ -36,5 +36,5 @@ UFile (package = ) [public abstract interface Callback {...]
                                                         UCallExpression (kind = UastCallKind(name='constructor_call'), argCount = 1)) [<init>("")] : PsiType:UnsupportedOperationException
                                                             UIdentifier (Identifier (UnsupportedOperationException)) [UIdentifier (Identifier (UnsupportedOperationException))]
                                                             USimpleNameReferenceExpression (identifier = <init>, resolvesTo = UnsupportedOperationException) [<init>] : PsiType:UnsupportedOperationException
-                                                            ULiteralExpression (value = "") [""] : PsiType:String
+                                                            UPolyadicExpression (value = "") [""] : PsiType:String
                                             UMethod (name = Model$1$1) [fun Model$1$1() = UastEmptyExpression]
diff --git a/plugins/uast-kotlin/testData/WhenAndDestructing.log.txt b/plugins/uast-kotlin/testData/WhenAndDestructing.log.txt
index cd9124b0aab..b62fb8cccba 100644
--- a/plugins/uast-kotlin/testData/WhenAndDestructing.log.txt
+++ b/plugins/uast-kotlin/testData/WhenAndDestructing.log.txt
@@ -9,16 +9,20 @@ UFile (package = )
                         UCallExpression (kind = UastCallKind(name='method_call'), argCount = 2))
                             UIdentifier (Identifier (listOf))
                             USimpleNameReferenceExpression (identifier = listOf, resolvesTo = null)
-                            ULiteralExpression (value = "1")
-                            ULiteralExpression (value = "2")
+                            UPolyadicExpression (operator = +)
+                                ULiteralExpression (value = "1")
+                            UPolyadicExpression (operator = +)
+                                ULiteralExpression (value = "2")
                 USwitchExpression
                     USimpleNameReferenceExpression (identifier = string)
                     UExpressionList (when)
                         USwitchClauseExpressionWithBody
-                            ULiteralExpression (value = "aaaa")
+                            UPolyadicExpression (operator = +)
+                                ULiteralExpression (value = "aaaa")
                             UExpressionList (when_entry)
                                 UReturnExpression
-                                    ULiteralExpression (value = "bindingContext")
+                                    UPolyadicExpression (operator = +)
+                                        ULiteralExpression (value = "bindingContext")
                                 UBreakExpression (label = null)
                         USwitchClauseExpressionWithBody
                             UExpressionList (when_entry)
diff --git a/plugins/uast-kotlin/testData/WhenIs.log.txt b/plugins/uast-kotlin/testData/WhenIs.log.txt
index 0941dd1c738..0ce880d5d62 100644
--- a/plugins/uast-kotlin/testData/WhenIs.log.txt
+++ b/plugins/uast-kotlin/testData/WhenIs.log.txt
@@ -20,5 +20,6 @@ UFile (package = )
                                     USimpleNameReferenceExpression (identifier = it)
                                     UTypeReferenceExpression (name = java.lang.String)
                                 UExpressionList (when_entry)
-                                    ULiteralExpression (value = "<error>")
+                                    UPolyadicExpression (operator = +)
+                                        ULiteralExpression (value = "<error>")
                                     UBreakExpression (label = null)
diff --git a/plugins/uast-kotlin/testData/WhenStringLiteral.log.txt b/plugins/uast-kotlin/testData/WhenStringLiteral.log.txt
index e689d23089e..5773cba2846 100644
--- a/plugins/uast-kotlin/testData/WhenStringLiteral.log.txt
+++ b/plugins/uast-kotlin/testData/WhenStringLiteral.log.txt
@@ -11,13 +11,16 @@ UFile (package = )
                 USimpleNameReferenceExpression (identifier = a)
                 UExpressionList (when)
                     USwitchClauseExpressionWithBody
-                        ULiteralExpression (value = "abc")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "abc")
                         UExpressionList (when_entry)
                             ULiteralExpression (value = 1)
                             UBreakExpression (label = null)
                     USwitchClauseExpressionWithBody
-                        ULiteralExpression (value = "def")
-                        ULiteralExpression (value = "ghi")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "def")
+                        UPolyadicExpression (operator = +)
+                            ULiteralExpression (value = "ghi")
                         UExpressionList (when_entry)
                             ULiteralExpression (value = 2)
                             UBreakExpression (label = null)
@@ -29,5 +32,7 @@ UFile (package = )
         UMethod (name = getB)
         UMethod (name = <no name provided>)
             UBlockExpression
-                ULiteralExpression (value = "abc1")
-                ULiteralExpression (value = "def1")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "abc1")
+                UPolyadicExpression (operator = +)
+                    ULiteralExpression (value = "def1")