package parser

Import Path
	go/parser (on go.dev)

Dependency Relation
	imports 12 packages, and imported by 5 packages


Involved Source Files

	    interface.go
	
		Package parser implements a parser for Go source files.
		
		The [ParseFile] function reads file input from a string, []byte, or
		io.Reader, and produces an [ast.File] representing the complete
		abstract syntax tree of the file.
		
		The [ParseExprFrom] function reads a single source-level expression and
		produces an [ast.Expr], the syntax tree of the expression.
		
		The parser accepts a larger language than is syntactically permitted by
		the Go spec, for simplicity, and for improved robustness in the presence
		of syntax errors. For instance, in method declarations, the receiver is
		treated like an ordinary parameter list and thus may contain multiple
		entries where the spec permits exactly one. Consequently, the corresponding
		field in the AST (ast.FuncDecl.Recv) field is not restricted to one entry.
		
		Applications that need to parse one or more complete packages of Go
		source code may find it more convenient not to interact directly
		with the parser but instead to use the Load function in package
		[golang.org/x/tools/go/packages].

	    resolver.go


Code Examples

	
		package main
		
		import (
			"fmt"
			"go/parser"
			"go/token"
		)
		
		func main() {
			fset := token.NewFileSet() // positions are relative to fset
		
			src := `package foo
		
		import (
			"fmt"
			"time"
		)
		
		func bar() {
			fmt.Println(time.Now())
		}`
		
			// Parse src but stop after processing the imports.
			f, err := parser.ParseFile(fset, "", src, parser.ImportsOnly)
			if err != nil {
				fmt.Println(err)
				return
			}
		
			// Print the imports from the file's AST.
			for _, s := range f.Imports {
				fmt.Println(s.Path.Value)
			}
		
		}




Package-Level Type Names (only one)


	/* sort by:  |  */
	
		A Mode value is a set of flags (or 0).
		They control the amount of source code parsed and other optional
		parser functionality.

		
			func ParseDir(fset *token.FileSet, path string, filter func(fs.FileInfo) bool, mode Mode) (pkgs map[string]*ast.Package, first error)
			func ParseExprFrom(fset *token.FileSet, filename string, src any, mode Mode) (expr ast.Expr, err error)
			func ParseFile(fset *token.FileSet, filename string, src any, mode Mode) (f *ast.File, err error)
		
			const AllErrors
			const DeclarationErrors
			const ImportsOnly
			const PackageClauseOnly
			const ParseComments
			const SkipObjectResolution
			const SpuriousErrors
			const Trace




Package-Level Functions (total 4)


	
		ParseDir calls [ParseFile] for all files with names ending in ".go" in the
		directory specified by path and returns a map of package name -> package
		AST with all the packages found.
		
		If filter != nil, only the files with [fs.FileInfo] entries passing through
		the filter (and ending in ".go") are considered. The mode bits are passed
		to [ParseFile] unchanged. Position information is recorded in fset, which
		must not be nil.
		
		If the directory couldn't be read, a nil map and the respective error are
		returned. If a parse error occurred, a non-nil but incomplete map and the
		first error encountered are returned.
		
		Deprecated: ParseDir does not consider build tags when associating
		files with packages. For precise information about the relationship
		between packages and files, use golang.org/x/tools/go/packages,
		which can also optionally parse and type-check the files too.


	
		ParseExpr is a convenience function for obtaining the AST of an expression x.
		The position information recorded in the AST is undefined. The filename used
		in error messages is the empty string.
		
		If syntax errors were found, the result is a partial AST (with [ast.Bad]* nodes
		representing the fragments of erroneous source code). Multiple errors are
		returned via a scanner.ErrorList which is sorted by source position.


	
		ParseExprFrom is a convenience function for parsing an expression.
		The arguments have the same meaning as for [ParseFile], but the source must
		be a valid Go (type or value) expression. Specifically, fset must not
		be nil.
		
		If the source couldn't be read, the returned AST is nil and the error
		indicates the specific failure. If the source was read but syntax
		errors were found, the result is a partial AST (with [ast.Bad]* nodes
		representing the fragments of erroneous source code). Multiple errors
		are returned via a scanner.ErrorList which is sorted by source position.


	
		ParseFile parses the source code of a single Go source file and returns
		the corresponding [ast.File] node. The source code may be provided via
		the filename of the source file, or via the src parameter.
		
		If src != nil, ParseFile parses the source from src and the filename is
		only used when recording position information. The type of the argument
		for the src parameter must be string, []byte, or [io.Reader].
		If src == nil, ParseFile parses the file specified by filename.
		
		The mode parameter controls the amount of source text parsed and
		other optional parser functionality. If the [SkipObjectResolution]
		mode bit is set (recommended), the object resolution phase of
		parsing will be skipped, causing File.Scope, File.Unresolved, and
		all Ident.Obj fields to be nil. Those fields are deprecated; see
		[ast.Object] for details.
		
		Position information is recorded in the file set fset, which must not be
		nil.
		
		If the source couldn't be read, the returned AST is nil and the error
		indicates the specific failure. If the source was read but syntax
		errors were found, the result is a partial AST (with [ast.Bad]* nodes
		representing the fragments of erroneous source code). Multiple errors
		are returned via a scanner.ErrorList which is sorted by source position.




Package-Level Constants (total 8)


	const AllErrors Mode = 32 // report all errors (not just the first 10 on different lines)
	const DeclarationErrors Mode = 16 // report declaration errors
	const ImportsOnly Mode = 2 // stop parsing after import declarations
	const PackageClauseOnly Mode = 1 // stop parsing after package clause
	const ParseComments Mode = 4 // parse comments and add them to AST
	const SkipObjectResolution Mode = 64 // skip deprecated identifier resolution; see ParseFile
	const SpuriousErrors Mode = 32 // same as AllErrors, for backward-compatibility
	const Trace Mode = 8 // print a trace of parsed productions