Set internal linkage and keeping default visibility for anonymous functions

testdata/generics.go

@@ -1,11 +1,19 @@
 package main
 
+import (
+	"github.com/tinygo-org/tinygo/testdata/generics/testa"
+	"github.com/tinygo-org/tinygo/testdata/generics/testb"
+)
+
 func main() {
 	println("add:", Add(3, 5))
 	println("add:", Add(int8(3), 5))
 
 	var c C[int]
 	c.F() // issue 2951
+
+	testa.Test()
+	testb.Test()
 }
 
 type Integer interface {

testdata/generics.txt

@@ -1,2 +1,6 @@
 add: 8
 add: 8
+value: 101
+value: 101
+value: 501
+value: 501

testdata/generics/testa/testa.go

@@ -0,0 +1,20 @@
+package testa
+
+import (
+	"github.com/tinygo-org/tinygo/testdata/generics/value"
+)
+
+func Test() {
+	v := value.New(1)
+	vm := value.Map(v, Plus100)
+	vm.Get(callback, callback)
+}
+
+func callback(v int) {
+	println("value:", v)
+}
+
+// Plus100 is a `Transform` that adds 100 to `value`.
+func Plus100(value int) int {
+	return value + 100
+}

testdata/generics/testb/testb.go

@@ -0,0 +1,20 @@
+package testb
+
+import (
+	"github.com/tinygo-org/tinygo/testdata/generics/value"
+)
+
+func Test() {
+	v := value.New(1)
+	vm := value.Map(v, Plus500)
+	vm.Get(callback, callback)
+}
+
+func callback(v int) {
+	println("value:", v)
+}
+
+// Plus500 is a `Transform` that adds 500 to `value`.
+func Plus500(value int) int {
+	return value + 500
+}

testdata/generics/value/value.go

@@ -0,0 +1,53 @@
+package value
+
+type (
+	Value[T any] interface {
+		Get(Callback[T], Callback[T])
+	}
+
+	Callback[T any] func(T)
+
+	Transform[S any, D any] func(S) D
+)
+
+func New[T any](v T) Value[T] {
+	return &value[T]{
+		v: v,
+	}
+}
+
+type value[T any] struct {
+	v T
+}
+
+func (v *value[T]) Get(fn1, fn2 Callback[T]) {
+	// For example purposes.
+	// Normally would be asynchronous callback.
+	fn1(v.v)
+	fn2(v.v)
+}
+
+func Map[S, D any](v Value[S], tx Transform[S, D]) Value[D] {
+	return &mapper[S, D]{
+		v:  v,
+		tx: tx,
+	}
+}
+
+type mapper[S, D any] struct {
+	v  Value[S]
+	tx Transform[S, D]
+}
+
+func (m *mapper[S, D]) Get(fn1, fn2 Callback[D]) {
+	// two callbacks are passed to generate more than
+	// one anonymous function symbol name.
+	m.v.Get(func(v S) {
+		// anonymous function inside of anonymous function.
+		func() {
+			fn1(m.tx(v))
+		}()
+	}, func(v S) {
+		fn2(m.tx(v))
+	})
+}