diff --git a/grammar/src/class.grm b/grammar/src/class.grm
index c7d533f6925..abe86e7dd97 100644
--- a/grammar/src/class.grm
+++ b/grammar/src/class.grm
@@ -16,19 +16,28 @@ class
       "wraps"?
       ("(" primaryConstructorParameter{","} ")")?
       (":" delegationSpecifier{","})?
-      ("where" typeConstraint{","})?  // Syntax is questionable
+      ("where" typeConstraint{","})?  // TODO: Syntax is questionable
       classBody?
   ;
 
-classBody
-  : ("{" memberDeclaration{","} "}"
-  ;
-
 classModifier
   : accessModifier
   : "abstract"
-  : "interface" // TODO: better name
-  : "sealed"
+  : "virtual"
+  : "enum"
+  : "extendable" // TODO: open?
+  // sealed by default
+  ;
+
+accessModifier
+  : "private"
+  : "protected"
+  : "public"
+  : "internal"
+  ;  
+
+classBody
+  : ("{" memberDeclaration{","} "}")?
   ;
 
 delegationSpecifier
@@ -44,8 +53,13 @@ typeParameter
   : varianceAnnotation? SimpleName (":" userType)?
   ;
 
+varianceAnnotation
+  : "in"
+  : "out"
+  ;
+
 typeConstraint
-  : userType ":" (userType | "this") 
+  : userType ":" (userType | "this") // "this" for self-type 
   // TODO: other constraints, maybe
   ;
 
diff --git a/grammar/src/class_members.grm b/grammar/src/class_members.grm
index 2fd7ae9de5d..3ee92cc10a7 100644
--- a/grammar/src/class_members.grm
+++ b/grammar/src/class_members.grm
@@ -39,10 +39,6 @@ memberDeclaration
   : class
   ;
 
-decomposer  // TODO: consider other names
-  : "decomposer" SimpleName "(" SimpleName{","} ")" // Public properties only
-  ;
-
 classObject
   : "class" objectLiteral
   ;
@@ -51,38 +47,57 @@ constructor
   : accessModifier? "this" functionParameters (":" initializers) block
   ;
 
+functionParameters
+  : "(" functionParameter{","}? ")" // default values
+  ;
+
+functionParameter
+  : parameterKind parameter ("=" expression)?
+  ;
+
+parameterKind
+  : "lazy"
+  : "out"
+  : "ref"
+  ;
+
 initializers
-  : "this" functionArguments
+  : "this" valueArguments
   : constructorInvocation // type parameters may (must?) be omitted
   ;
 
-super
-  : "super" "<" name ">"
+block
+  : "{" expression "}"
+  ;
+
+decomposer  // TODO: consider other names
+  : "decomposer" SimpleName "(" SimpleName{","} ")" // Public properties only
   ;
 
 method
-  : methodModifier* "fun" functionRest
+  : memberModifier* "fun" functionRest
+  ;
+
+memberModifier
+  : accessModifier
+  : "override"
+  : "virtual"
+  : "abstract"
+  : // TODO: inline
   ;
 
 functionRest
   : SimpleName typeParameters? functionParameters (":" type)? functionBody?
   ;
 
-functionParameters
-  : "(" ((parameter ("=" expression)?){","})? ")" // default values
-  ;
-
-block
-  : "{" expression* "}"
-  ;
-
 functionBody
   : block
   : "=" expression
   ;
 
 property
-  : propertyModifier* ("val" | "var")
+  : memberModifier* "lazy"? ("val" | "var") propertyRest
+  ;
 
 propertyRest
   : SimpleName (":" type)? ("=" expression)?
@@ -90,10 +105,13 @@ propertyRest
   ;
 
 getter
-  : methodModifier* "get" "(" ")" functionBody
+  : memberModifier* "get" "(" ")" functionBody
   ;
 
 setter
-  : methodModifier* "set" "(" parameter ")" functionBody
+  : memberModifier* "set" "(" parameter ")" functionBody
   ;
 
+parameter
+  : SimpleName ":" type
+  ;
\ No newline at end of file
diff --git a/grammar/src/control.grm b/grammar/src/control.grm
index 84e5b1329d6..0a80375a059 100644
--- a/grammar/src/control.grm
+++ b/grammar/src/control.grm
@@ -2,6 +2,12 @@ if
   : "if" "(" expression ")" expression ("else" expression)?
   ;
 
+loop
+  : for
+  : while
+  : doWhile
+  ;
+
 for
   : "for" "(" valOrVar? (SimpleName | parameter) "in" expression ")" expression
   ;
diff --git a/grammar/src/expressions.grm b/grammar/src/expressions.grm
index 6928ea7ef97..0fe5ec86337 100644
--- a/grammar/src/expressions.grm
+++ b/grammar/src/expressions.grm
@@ -7,15 +7,32 @@ expression
   : mapLiteral
   : range
   : "null"
-  : "this"
+  : "this" ("<" type ">")?
   : memberAccessExpression
   : expressionWithPrecedences
   : match
   : if
-  : "typeof"
+  : "typeof" // TODO: another keyword
   : "new" constructorInvocation // TODO: Do we need "new"?, see factory methods
   : objectLiteral
+  : declaration
   : jump
+  : loop
+  // block is syntactically equivalent to a functionLiteral with no parameters
+  ;
+
+literalConstant
+  : "true" | "false"
+  : StringWithTemplates
+  : NoEscapeString
+  : IntegerLiteral
+  : HexadecimalLiteral
+  : CharacterLiteral
+  ;
+
+declaration
+  : function
+  : property
   ;
 
 expressionWithPrecedences // See the precedence table, everything associates to the left
@@ -25,6 +42,11 @@ expressionWithPrecedences // See the precedence table, everything associates to
   : unOpExpression
   : castExpression
   : typingExpression
+  : memberAccessExpression
+  ;
+
+memberAccessExpression
+  : (expression ".")? memberAccess
   ;
 
 typingExpression
@@ -32,18 +54,15 @@ typingExpression
   ;
 
 typingOperation
-  : "as" : "is" : "isnot"
+  : "as"
+  : "is"
+  : "isnot"
   ;
 
 binOpExpression
   : expression binaryOperation expression // see priorities
   ;
 
-unOpExpression
-  : expression postfixUnaryOperation
-  : prefixUnaryOperation expression
-  ;
-
 binaryOperation // Decreasing precedence
   // .
   // unary
@@ -68,6 +87,11 @@ assignment
   : memberAccessExpression assignmentOperator expression // Assignment to functions prohibited by a semantic check
   ;
 
+unOpExpression
+  : expression postfixUnaryOperation
+  : prefixUnaryOperation expression
+  ;
+
 prefixUnaryOperation
   : "-" : "+"
   : "++" : "--"
@@ -120,11 +144,11 @@ constructorInvocation
   ;
 
 listLiteral
-  : "[" expression{","} "]"
+  : "[" expression{","}? "]"
   ;
 
 mapLiteral
-  : "[" mapEntryLiteral ("," mapEntryLiteral)* "]"
+  : "[" mapEntryLiteral{","} "]"
   : "[" ":" "]"
   ;
 
@@ -132,25 +156,10 @@ mapEntryLiteral
   : expression ":" expression
   ;
 
-literalConstant
-  : booleanLiteral
-  : IntegerLiteral
-  : HexadecimalLiteral
-  : CharacterLiteral
-  : SingleLineStringLiteral
-  : SingleLineStringTemplate
-  : MultiLineStringLiteral
-  : MultiLineStringTemplate
-  ;
-
 range
   : "[" expression ".." expression "]"
   ;
 
-memberAccessExpression
-  : (expression ".")? memberAccess
-  ;
-
 memberAccess
   : functionCall
   : fieldOrPropertyAccess
@@ -166,7 +175,7 @@ arrayAccess
   ;
 
 objectLiteral
-  : "object" delegationSpecifier{","} classBody?
+  : "object" delegationSpecifier{","}? classBody?
   ;
 
 /* Factory methods:
diff --git a/grammar/src/extension.grm b/grammar/src/extension.grm
index d79baa79817..b919f270664 100644
--- a/grammar/src/extension.grm
+++ b/grammar/src/extension.grm
@@ -6,7 +6,7 @@ extension
   ;
 
 completeExtension
-  : accessModifier? "extension" SimpleName? typeParameters? "for" type classBody?
+  : accessModifier? "extension" SimpleName? typeParameters? "for" type classBody? // properties cannot be lazy, cannot have backing fields
   ;
 
 extensionMethod
@@ -14,7 +14,7 @@ extensionMethod
   ;
 
 extensionProperty
-  : accessModifier? propertyModifier? ("val" | "var") type "." propertyRest
+  : accessModifier? propertyModifier? ("val" | "var") type "." propertyRest // Extension property cannot be lazy
   ;
 
 extensionDecomposer
diff --git a/grammar/src/lexical.grm b/grammar/src/lexical.grm
index 2368e558c62..9b98f837acd 100644
--- a/grammar/src/lexical.grm
+++ b/grammar/src/lexical.grm
@@ -5,7 +5,9 @@ IntegerLiteral : Digit+ "L"?
 [helper] HexDigit : Digit | ["A"-"F", "a"-"f"];
 HexadecimalLiteral : "0x" HexDigit+;
 
-StringWithPatterns : /*single-quoted string, $ can be escaped*/;
+CharacterLiteral : /*character as in Java*/
+
+StringWithTemplates : /*single-quoted string, $ can be escaped*/;
 NoEscapeString : /* @-prefixed string, maybe allow putting a bar for indentation correction */;
 
 /*
diff --git a/grammar/src/match.grm b/grammar/src/match.grm
index 2b88ee7fc4c..99c1e8ca479 100644
--- a/grammar/src/match.grm
+++ b/grammar/src/match.grm
@@ -14,6 +14,10 @@ pattern
   : decomposerPattern // labeled components are allowed
   ;
 
+constantPattern
+  : literalConstant
+  ;
+
 tuplePattern
   : "(" ((SimpleName "=")? pattern{","})? ")"
   ;
diff --git a/grammar/src/other.grm b/grammar/src/other.grm
index bc4806ee703..e69de29bb2d 100644
--- a/grammar/src/other.grm
+++ b/grammar/src/other.grm
@@ -1,15 +0,0 @@
-accessModifier
-  : "private"
-  : "protected"
-  : "public"
-  : "internal"
-  ;
-
-parameter
-  : SimpleName ":" type
-  // TODO: lazy, out, ref ...
-  ;
-
-functionArguments
-  : "(" (expression{","})* ")"
-  ;
diff --git a/grammar/src/toplevel.grm b/grammar/src/toplevel.grm
index 9e0abe9928e..9cec344a502 100644
--- a/grammar/src/toplevel.grm
+++ b/grammar/src/toplevel.grm
@@ -1,7 +1,10 @@
-jetlFile
+[start] jetlFile
   : preamble toplevelObject*
   ;
 
+[start] script
+  : expression
+
 preamble
   : namespaceHeader? import*
   ;
diff --git a/grammar/src/types.grm b/grammar/src/types.grm
index 017f0d2beb9..bd13fa46ff2 100644
--- a/grammar/src/types.grm
+++ b/grammar/src/types.grm
@@ -16,13 +16,7 @@ type
   ;
 
 userType
-  : name ("<" (projectionSpecifier type){","} ">")?
-  ;
-
-projectionSpecifier
-  : "in"
-  : "out"
-  : empty
+  : SimpleName{"."} ("<" (varianceSpecifier? type){","} ">")?
   ;
 
 functionType