Add a link to hostConfiguration from compilation and evaluation ones

also add possibility to supply functional defaults for keys in PropertiesCollection

libraries/scripting/common/src/kotlin/script/experimental/api/scriptCompilation.kt

@@ -9,6 +9,7 @@ package kotlin.script.experimental.api
 
 import java.io.Serializable
 import kotlin.reflect.KClass
+import kotlin.script.experimental.host.ScriptingHostConfiguration
 import kotlin.script.experimental.util.PropertiesCollection
 
 interface ScriptCompilationConfigurationKeys
@@ -113,6 +114,11 @@ val ScriptCompilationConfigurationKeys.refineConfigurationBeforeCompiling by Pro
  */
 val ScriptCompilationConfigurationKeys.sourceFragments by PropertiesCollection.key<List<ScriptSourceNamedFragment>>()
 
+/**
+ * Scripting host configuration
+ */
+val ScriptCompilationConfigurationKeys.hostConfiguration by PropertiesCollection.key<ScriptingHostConfiguration>()
+
 /**
  * The sub-builder DSL for configuring refinement callbacks
  */

libraries/scripting/common/src/kotlin/script/experimental/api/scriptEvaluation.kt

@@ -9,6 +9,7 @@ package kotlin.script.experimental.api
 
 import java.io.Serializable
 import kotlin.reflect.KClass
+import kotlin.script.experimental.host.ScriptingHostConfiguration
 import kotlin.script.experimental.util.PropertiesCollection
 
 interface ScriptEvaluationConfigurationKeys
@@ -67,6 +68,11 @@ val ScriptEvaluationConfigurationKeys.scriptsInstancesSharingMap by PropertiesCo
  */
 val ScriptEvaluationConfigurationKeys.scriptsInstancesSharing by PropertiesCollection.key<Boolean>(false)
 
+/**
+ * Scripting host configuration
+ */
+val ScriptEvaluationConfigurationKeys.hostConfiguration by PropertiesCollection.key<ScriptingHostConfiguration>()
+
 /**
  * The callback that will be called on the script compilation immediately before starting the compilation
  */