print AST for Go file

printAST.go

package main

import (
	"go/ast"
	"go/parser"
	"go/token"
	"io/ioutil"
	"os"
)

func main() {
	src, err := ioutil.ReadFile(os.Args[1])
	if err != nil {
		panic(err)
	}

	// Create the AST by parsing src.
	fset := token.NewFileSet() // positions are relative to fset
	f, err := parser.ParseFile(fset, "", string(src), 0)
	if err != nil {
		panic(err)
	}

	// Print the AST.
	ast.Print(fset, f)
}