The reflect package of Go 1.1 adds functions SliceOf, ChanOf，and MakeFunc.
With the help of these new functions, we can do things similar to Python's map, list, iterator comprehension, and decorator in Go.
The followings is a simple demonstration of functionality similar to Python's map function and list comprehension.

	package main
	import (
	"fmt"
	"reflect"
	)
	type duck interface{}
	// Python like map function
	func Map(fn duck, list duck) duck {
	fnType, fnValue := reflect.TypeOf(fn), reflect.ValueOf(fn)
	listValue := reflect.ValueOf(list)
	// fmt.Println("assert", fnType.NumOut() == 1, fnType.NumIn() == 1, fnType.In(0) == listType.Elem())
	rtnType := reflect.SliceOf(fnType.Out(0))
	rtnValue := reflect.MakeSlice(rtnType, 0, listValue.Len())
	for i := 0; i < listValue.Len(); i++ {
	in := []reflect.Value{listValue.Index(i)}
	rtnValue = reflect.Append(rtnValue, fnValue.Call(in)[0])
	}
	return rtnValue.Interface()
	}
	// Python like range function
	func Range(n int) []int {
	rtn := make([]int, 0, n)
	for i := 0; i < n; i++ {
	rtn = append(rtn, i)
	}
	return rtn
	}
	type in chan duck
	// Python like list comprehension construction
	func List(fn func(x in)) duck {
	x := make(chan duck)
	go func() { fn(x); close(x) }()
	first := <-x
	rtnType := reflect.SliceOf(reflect.TypeOf(first))
	rtnValue := reflect.MakeSlice(rtnType, 0, 0)
	rtnValue = reflect.Append(rtnValue, reflect.ValueOf(first))
	for v := range x {
	rtnValue = reflect.Append(rtnValue, reflect.ValueOf(v))
	}
	return rtnValue.Interface()
	}
	func main() {
	fn := func(x int) string { return fmt.Sprintf("%dx%d=%d", x, x, x*x) }
	// Compare to rtn = map(fn, range(10))
	rtn := Map(fn, Range(10)).([]string)
	fmt.Println(rtn)
	// Compare to rtn2 = [ i * i for i in range(5)]
	rtn2 := List(func(x in) {for i := 0; i < 5; i++ { x <- i * i }}).([]int)
	fmt.Println(rtn2)
	}

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