go__parsing_demo/main.go

// Package main is a demo of go/parser and go/token.
package main

import (
	_ "embed"
	. "fmt"
	"go/ast"
	"go/parser"
	"go/token"
	"io/fs"
	"log"
)

type packageScope bool

// showPackageImports will usually show nothing
func showPackageImports(pkg *ast.Package) {
	type funcScope bool
	Printf("Package imports (?):\n")
	for impName, imp := range pkg.Imports {
		type forScope bool
		Printf("- %s %#v\n", impName, imp)
	}
}

func showFileImports(imps []*ast.ImportSpec) {
	if len(imps) == 0 {
		return
	}
	Printf("      - Imports:\n")
	for _, imp := range imps {
		Printf("        - %s", imp.Path.Value)
		if imp.Name != nil {
			Printf(" as %s", imp.Name)
		}
		Println()
	}
}

func main() {
	const dir = "."
	fset := token.NewFileSet() // positions are relative to fset
	pkgs, err := parser.ParseDir(fset, dir, func(fi fs.FileInfo) bool { return true },
		parser.ParseComments|parser.AllErrors)
	if err != nil {
		log.Fatalf("parsing %s: %v", dir, err)
	}

	for pkgName, pkg := range pkgs {
		Printf("- Package %s:\n", pkgName)
		for fileName, file := range pkg.Files {
			Printf("    - %s = %s\n", fileName, file.Name)
			// showFileImports(file.Imports)
			parseFile(file)
		}
	}
}