Add util.FuncName

util/func.go

@@ -0,0 +1,17 @@
+package util
+
+import (
+	"reflect"
+	"runtime"
+	"strings"
+)
+
+// FuncName makes a best effort attempt to return the string name of the
+// passed function. Anonymous functions are named "funcN" where N is the
+// order of appearance within the current scope. Note that this function
+// will panic if not passed a function.
+func FuncName(i any) string {
+	p := runtime.FuncForPC(reflect.ValueOf(i).Pointer())
+	n := strings.Split(p.Name(), `.`)
+	return n[len(n)-1]
+}

util/func_test.go

@@ -0,0 +1,25 @@
+package util_test
+
+import (
+	"github.com/rwxrob/bonzai/each"
+	"github.com/rwxrob/bonzai/fn"
+	"github.com/rwxrob/bonzai/util"
+)
+
+func Foo() {}
+
+func ExampleFuncName() {
+
+	f1 := func() {}
+	f2 := func() {}
+
+	// Foo is defined outside of the ExampleFuncName
+
+	each.Println(fn.Map([]any{f1, f2, Foo, util.Files}, util.FuncName))
+
+	// Output:
+	// func1
+	// func2
+	// Foo
+	// Files
+}