Replace deprecated join with joinToString in idl2k

libraries/tools/idl2k/src/main/kotlin/render.kt

@@ -65,7 +65,7 @@ private fun Appendable.renderArgumentsDeclaration(args: List<GenerateAttribute>,
             }
         }.joinTo(this, ", ", "(", ")")
 
-private fun renderCall(call: GenerateFunctionCall) = "${call.name.replaceKeywords()}(${call.arguments.map { it.replaceKeywords() }.join(", ")})"
+private fun renderCall(call: GenerateFunctionCall) = "${call.name.replaceKeywords()}(${call.arguments.joinToString(", ") { it.replaceKeywords() }})"
 
 private fun Appendable.renderFunctionDeclaration(f: GenerateFunction, override: Boolean, commented: Boolean, level: Int = 1) {
     indent(commented, level)

libraries/tools/idl2k/src/main/kotlin/types.kt

@@ -29,7 +29,7 @@ data class SimpleType(val type: String, override val nullable: Boolean) : Type {
 }
 data class FunctionType(val parameterTypes : List<Attribute>, val returnType : Type, override val nullable: Boolean) : Type {
     override fun render() = if (nullable) "(${renderImpl()})?" else renderImpl()
-    private fun renderImpl() = "(${parameterTypes.map { it.type.render() }.join(", ")}) -> ${returnType.render()}"
+    private fun renderImpl() = "(${parameterTypes.joinToString(", ") { it.type.render() }}) -> ${returnType.render()}"
 }
 
 val FunctionType.arity : Int
@@ -42,7 +42,7 @@ class UnionType(val namespace: String, types: Collection<Type>, override val nul
     operator fun contains(type: Type) = type in memberTypes
     override fun equals(other: Any?): Boolean = other is UnionType && memberTypes == other.memberTypes
     override fun hashCode(): Int = memberTypes.hashCode()
-    override fun toString(): String = memberTypes.map { it.toString() }.join(", ", "Union<", ">")
+    override fun toString(): String = memberTypes.joinToString(", ", "Union<", ">")
 
     override fun render(): String = name.appendNullabilitySuffix(this)