package printer

Import Path
	go/printer (on

Dependency Relation
	imports 15 packages, and imported by one package

Involved Source Files comment.go gobuild.go nodes.go Package printer implements printing of AST nodes.
Code Examples package main import ( "bytes" "fmt" "go/ast" "go/parser" "go/printer" "go/token" "strings" ) func parseFunc(filename, functionname string) (fun *ast.FuncDecl, fset *token.FileSet) { fset = token.NewFileSet() if file, err := parser.ParseFile(fset, filename, nil, 0); err == nil { for _, d := range file.Decls { if f, ok := d.(*ast.FuncDecl); ok && f.Name.Name == functionname { fun = f return } } } panic("function not found") } func printSelf() { // Parse source file and extract the AST without comments for // this function, with position information referring to the // file set fset. funcAST, fset := parseFunc("example_test.go", "printSelf") // Print the function body into buffer buf. // The file set is provided to the printer so that it knows // about the original source formatting and can add additional // line breaks where they were present in the source. var buf bytes.Buffer printer.Fprint(&buf, fset, funcAST.Body) // Remove braces {} enclosing the function body, unindent, // and trim leading and trailing white space. s := buf.String() s = s[1 : len(s)-1] s = strings.TrimSpace(strings.ReplaceAll(s, "\n\t", "\n")) // Print the cleaned-up body text to stdout. fmt.Println(s) } func main() { printSelf() }
Package-Level Type Names (total 3)
/* sort by: | */
A CommentedNode bundles an AST node and corresponding comments. It may be provided as argument to any of the [Fprint] functions. Comments []*ast.CommentGroup // *ast.File, or ast.Expr, ast.Decl, ast.Spec, or ast.Stmt
A Config node controls the output of Fprint. // default: 0 (all code is indented at least by this much) // default: 0 // default: 8 Fprint "pretty-prints" an AST node to output for a given configuration cfg. Position information is interpreted relative to the file set fset. The node type must be *[ast.File], *[CommentedNode], [][ast.Decl], [][ast.Stmt], or assignment-compatible to [ast.Expr], [ast.Decl], [ast.Spec], or [ast.Stmt].
A Mode value is a set of flags (or 0). They control printing. const RawFormat const SourcePos const TabIndent const UseSpaces
Package-Level Functions (only one)
Fprint "pretty-prints" an AST node to output. It calls [Config.Fprint] with default settings. Note that gofmt uses tabs for indentation but spaces for alignment; use format.Node (package go/format) for output that matches gofmt.
Package-Level Constants (total 4)
const RawFormat Mode = 1 // do not use a tabwriter; if set, UseSpaces is ignored
const SourcePos Mode = 8 // emit //line directives to preserve original source positions
const TabIndent Mode = 2 // use tabs for indentation independent of UseSpaces
const UseSpaces Mode = 4 // use spaces instead of tabs for alignment