From 681cfebb0b23a188df4b79f6a83cec985dcbd019 Mon Sep 17 00:00:00 2001 From: Andrew Gerrand Date: Wed, 28 Apr 2010 12:36:39 +1000 Subject: Wiki codelab, complete with tests. R=r, rsc, gri CC=golang-dev http://codereview.appspot.com/887045 --- doc/codelab/wiki/srcextract.go | 73 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 doc/codelab/wiki/srcextract.go (limited to 'doc/codelab/wiki/srcextract.go') diff --git a/doc/codelab/wiki/srcextract.go b/doc/codelab/wiki/srcextract.go new file mode 100644 index 000000000..607375183 --- /dev/null +++ b/doc/codelab/wiki/srcextract.go @@ -0,0 +1,73 @@ +package main + +import ( + "bytes" + "flag" + "go/parser" + "go/printer" + "go/ast" + "log" + "os" +) + +var ( + srcFn = flag.String("src", "", "source filename") + getName = flag.String("name", "", "func/type name to output") + html = flag.Bool("html", true, "output HTML") + showPkg = flag.Bool("pkg", false, "show package in output") +) + +func main() { + // handle input + flag.Parse() + if *srcFn == "" || *getName == "" { + flag.Usage() + os.Exit(2) + } + // load file + file, err := parser.ParseFile(*srcFn, nil, nil, 0) + if err != nil { + log.Exit(err) + } + // create printer + p := &printer.Config{ + Mode: 0, + Tabwidth: 8, + Styler: nil, + } + if *html { + p.Mode = printer.GenHTML + } + // create filter + filter := func(name string) bool { + return name == *getName + } + // filter + if !ast.FilterFile(file, filter) { + os.Exit(1) + } + b := new(bytes.Buffer) + p.Fprint(b, file) + // drop package declaration + if !*showPkg { + for { + c, err := b.ReadByte() + if c == '\n' || err != nil { + break + } + } + } + // drop leading newlines + for { + b, err := b.ReadByte() + if err != nil { + break + } + if b != '\n' { + os.Stdout.Write([]byte{b}) + break + } + } + // output + b.WriteTo(os.Stdout) +} -- cgit v1.2.3