README
¶
parser
-- import "github.com/robertkrimen/otto/parser"
Package parser implements a parser for JavaScript.
import (
"github.com/robertkrimen/otto/parser"
)
Parse and return an AST
filename := "" // A filename is optional
src := `
// Sample xyzzy example
(function(){
if (3.14159 > 0) {
console.log("Hello, World.");
return;
}
var xyzzy = NaN;
console.log("Nothing happens.");
return xyzzy;
})();
`
// Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
program, err := parser.ParseFile(nil, filename, src, 0)
Warning
The parser and AST interfaces are still works-in-progress (particularly where node types are concerned) and may change in the future.
Usage
func ParseFile
func ParseFile(fileSet *file.FileSet, filename string, src interface{}, mode Mode) (*ast.Program, error)
ParseFile parses the source code of a single JavaScript/ECMAScript source file and returns the corresponding ast.Program node.
If fileSet == nil, ParseFile parses source without a FileSet. If fileSet != nil, ParseFile first adds filename and src to fileSet.
The filename argument is optional and is used for labelling errors, etc.
src may be a string, a byte slice, a bytes.Buffer, or an io.Reader, but it MUST always be in UTF-8.
// Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
program, err := parser.ParseFile(nil, "", `if (abc > 1) {}`, 0)
func ParseFunction
func ParseFunction(parameterList, body string) (*ast.FunctionLiteral, error)
ParseFunction parses a given parameter list and body as a function and returns the corresponding ast.FunctionLiteral node.
The parameter list, if any, should be a comma-separated list of identifiers.
func ReadSource
func ReadSource(filename string, src interface{}) ([]byte, error)
func TransformRegExp
func TransformRegExp(pattern string) (string, error)
TransformRegExp transforms a JavaScript pattern into a Go "regexp" pattern.
re2 (Go) cannot do backtracking, so the presence of a lookahead (?=) (?!) or backreference (\1, \2, ...) will cause an error.
re2 (Go) has a different definition for \s: [\t\n\f\r ]. The JavaScript definition, on the other hand, also includes \v, Unicode "Separator, Space", etc.
If the pattern is invalid (not valid even in JavaScript), then this function returns the empty string and an error.
If the pattern is valid, but incompatible (contains a lookahead or backreference), then this function returns the transformation (a non-empty string) AND an error.
type Error
type Error struct {
Position file.Position
Message string
}
An Error represents a parsing error. It includes the position where the error occurred and a message/description.
func (Error) Error
func (self Error) Error() string
type ErrorList
type ErrorList []*Error
ErrorList is a list of *Errors.
func (*ErrorList) Add
func (self *ErrorList) Add(position file.Position, msg string)
Add adds an Error with given position and message to an ErrorList.
func (ErrorList) Err
func (self ErrorList) Err() error
Err returns an error equivalent to this ErrorList. If the list is empty, Err returns nil.
func (ErrorList) Error
func (self ErrorList) Error() string
Error implements the Error interface.
func (ErrorList) Len
func (self ErrorList) Len() int
func (ErrorList) Less
func (self ErrorList) Less(i, j int) bool
func (*ErrorList) Reset
func (self *ErrorList) Reset()
Reset resets an ErrorList to no errors.
func (ErrorList) Sort
func (self ErrorList) Sort()
func (ErrorList) Swap
func (self ErrorList) Swap(i, j int)
type Mode
type Mode uint
A Mode value is a set of flags (or 0). They control optional parser functionality.
const (
IgnoreRegExpErrors Mode = 1 << iota // Ignore RegExp compatibility errors (allow backtracking)
)
-- godocdown http://github.com/robertkrimen/godocdown
Documentation
¶
Overview ¶
Package parser implements a parser for JavaScript.
import (
"github.com/robertkrimen/otto/parser"
)
Parse and return an AST
filename := "" // A filename is optional
src := `
// Sample xyzzy example
(function(){
if (3.14159 > 0) {
console.log("Hello, World.");
return;
}
var xyzzy = NaN;
console.log("Nothing happens.");
return xyzzy;
})();
`
// Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
program, err := parser.ParseFile(nil, filename, src, 0)
Warning ¶
The parser and AST interfaces are still works-in-progress (particularly where node types are concerned) and may change in the future.
Index ¶
- func ParseFile(fileSet *file.FileSet, filename string, src interface{}, mode Mode) (*ast.Program, error)
- func ParseFunction(parameterList, body string) (*ast.FunctionLiteral, error)
- func ReadSource(filename string, src interface{}) ([]byte, error)
- func TransformRegExp(pattern string) (string, error)
- type Error
- type ErrorList
- func (self *ErrorList) Add(position file.Position, msg string)
- func (self ErrorList) Err() error
- func (self ErrorList) Error() string
- func (self ErrorList) Len() int
- func (self ErrorList) Less(i, j int) bool
- func (self *ErrorList) Reset()
- func (self ErrorList) Sort()
- func (self ErrorList) Swap(i, j int)
- type Mode
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func ParseFile ¶
func ParseFile(fileSet *file.FileSet, filename string, src interface{}, mode Mode) (*ast.Program, error)
ParseFile parses the source code of a single JavaScript/ECMAScript source file and returns the corresponding ast.Program node.
If fileSet == nil, ParseFile parses source without a FileSet. If fileSet != nil, ParseFile first adds filename and src to fileSet.
The filename argument is optional and is used for labelling errors, etc.
src may be a string, a byte slice, a bytes.Buffer, or an io.Reader, but it MUST always be in UTF-8.
// Parse some JavaScript, yielding a *ast.Program and/or an ErrorList
program, err := parser.ParseFile(nil, "", `if (abc > 1) {}`, 0)
func ParseFunction ¶
func ParseFunction(parameterList, body string) (*ast.FunctionLiteral, error)
ParseFunction parses a given parameter list and body as a function and returns the corresponding ast.FunctionLiteral node.
The parameter list, if any, should be a comma-separated list of identifiers.
func ReadSource ¶
func TransformRegExp ¶
TransformRegExp transforms a JavaScript pattern into a Go "regexp" pattern.
re2 (Go) cannot do backtracking, so the presence of a lookahead (?=) (?!) or backreference (\1, \2, ...) will cause an error.
re2 (Go) has a different definition for \s: [\t\n\f\r ]. The JavaScript definition, on the other hand, also includes \v, Unicode "Separator, Space", etc.
If the pattern is invalid (not valid even in JavaScript), then this function returns the empty string and an error.
If the pattern is valid, but incompatible (contains a lookahead or backreference), then this function returns the transformation (a non-empty string) AND an error.
Types ¶
type Error ¶
An Error represents a parsing error. It includes the position where the error occurred and a message/description.
Source Files