diff options
Diffstat (limited to 'parser.go')
| -rw-r--r-- | parser.go | 30 |
1 files changed, 18 insertions, 12 deletions
@@ -7,7 +7,13 @@ import ( "unicode/utf8" ) -type Parser func(*State) interface{} +type Node struct { + Token string + Children []*Node + Result interface{} +} + +type Parser func(*State) *Node // Parserish types are any type that can be turned into a Parser by Parsify // These currently include *Parser and string literals. @@ -27,13 +33,13 @@ type Parserish interface{} func Parsify(p Parserish) Parser { switch p := p.(type) { - case func(*State) interface{}: + case func(*State) *Node: return Parser(p) case Parser: return p case *Parser: // Todo: Maybe capture this stack and on nil show it? Is there a good error library to do this? - return func(ptr *State) interface{} { + return func(ptr *State) *Node { return (*p)(ptr) } case string: @@ -54,17 +60,17 @@ func ParsifyAll(parsers ...Parserish) []Parser { func ParseString(parser Parserish, input string) (result interface{}, remaining string, err error) { p := Parsify(parser) ps := &State{input, 0, Error{}} - result = p(ps) + ret := p(ps) if ps.Error.Expected != "" { return nil, ps.Get(), ps.Error } - return result, ps.Get(), nil + return ret.Result, ps.Get(), nil } func Exact(match string) Parser { - return func(ps *State) interface{} { + return func(ps *State) *Node { if !strings.HasPrefix(ps.Get(), match) { ps.ErrorHere(match) return nil @@ -72,7 +78,7 @@ func Exact(match string) Parser { ps.Advance(len(match)) - return match + return &Node{Token: match} } } @@ -131,7 +137,7 @@ func charsImpl(matcher string, stopOn bool, repetition ...int) Parser { min, max := parseRepetition(1, -1, repetition...) matches, ranges := parseMatcher(matcher) - return func(ps *State) interface{} { + return func(ps *State) *Node { matched := 0 for ps.Pos+matched < len(ps.Input) { if max != -1 && matched >= max { @@ -163,19 +169,19 @@ func charsImpl(matcher string, stopOn bool, repetition ...int) Parser { result := ps.Input[ps.Pos : ps.Pos+matched] ps.Advance(matched) - return result + return &Node{Token: result} } } var ws = Chars("\t\n\v\f\r \x85\xA0", 0) -func WS(ps *State) interface{} { +func WS(ps *State) *Node { ws(ps) return nil } func String(quote rune) Parser { - return func(ps *State) interface{} { + return func(ps *State) *Node { var r rune var w int var matched int @@ -200,7 +206,7 @@ func String(quote rune) Parser { if r == quote { ps.Advance(matched) - return result.String() + return &Node{Token: result.String()} } result.WriteRune(r) } |