I am still struggling with generating IR for calli...

# compiler

[Johannes Barop]

I am still struggling with generating IR for calling a lambda. For example for forEach. I have difficulties setting the "action" parameter.

This is the IR-dump I want to generate:

action: FUN_EXPR type=kotlin.Function1<String, kotlin.Unit> origin=LAMBDA
          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> (it:String) returnType:kotlin.Unit
            VALUE_PARAMETER name:it index:0 type:String
            BLOCK_BODY

However, I can't get it to create a FUN_EXPR of type kotlin.Function1<String, kotlin.Unit>. Is irFactory.buildFun the proper approach?

Thats the current code - which does not work -

putValueArgument(0, irBlock(
              origin = IrStatementOrigin.LAMBDA,
              resultType = context.irBuiltIns.unitType,
            ) {
              +pluginContext.irFactory.buildFun {
                name = Name.identifier("")
                type = context.irBuiltIns.getKFunctionType(
                  returnType = context.irBuiltIns.unitType,
                  parameterTypes = listOf(context.irBuiltIns.stringType)
                )
                visibility = DescriptorVisibilities.LOCAL
                modality = Modality.FINAL
                origin = IrDeclarationOrigin.LOCAL_FUNCTION_FOR_LAMBDA
              }.also {
                it.dispatchReceiverParameter = null
                it.extensionReceiverParameter = null
                it.body = irBlockBody { }
              }
            })

Which generates following IR

action: BLOCK type=kotlin.Unit origin=LAMBDA
          FUN LOCAL_FUNCTION_FOR_LAMBDA name: visibility:local modality:FINAL <> () returnType:<Uninitialized>
            BLOCK_BODY

Any hints or clues?

[rnett]

You need to create an instance of IrFunctionExpression, and pass that as the argument. This is a now quite out of date function I had to do that. Last time I was working with IR you also had to explicitly set the return type of the lambda