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diff --git a/vendor/github.com/tdewolff/parse/v2/css/README.md b/vendor/github.com/tdewolff/parse/v2/css/README.md new file mode 100644 index 000000000..02797a711 --- /dev/null +++ b/vendor/github.com/tdewolff/parse/v2/css/README.md @@ -0,0 +1,170 @@ +# CSS [](https://pkg.go.dev/github.com/tdewolff/parse/v2/css?tab=doc) + +This package is a CSS3 lexer and parser written in [Go][1]. Both follow the specification at [CSS Syntax Module Level 3](http://www.w3.org/TR/css-syntax-3/). The lexer takes an io.Reader and converts it into tokens until the EOF. The parser returns a parse tree of the full io.Reader input stream, but the low-level `Next` function can be used for stream parsing to returns grammar units until the EOF. + +## Installation +Run the following command + + go get -u github.com/tdewolff/parse/v2/css + +or add the following import and run project with `go get` + + import "github.com/tdewolff/parse/v2/css" + +## Lexer +### Usage +The following initializes a new Lexer with io.Reader `r`: +``` go +l := css.NewLexer(parse.NewInput(r)) +``` + +To tokenize until EOF an error, use: +``` go +for { + tt, text := l.Next() + switch tt { + case css.ErrorToken: + // error or EOF set in l.Err() + return + // ... + } +} +``` + +All tokens (see [CSS Syntax Module Level 3](http://www.w3.org/TR/css3-syntax/)): +``` go +ErrorToken // non-official token, returned when errors occur +IdentToken +FunctionToken // rgb( rgba( ... +AtKeywordToken // @abc +HashToken // #abc +StringToken +BadStringToken +URLToken // url( +BadURLToken +DelimToken // any unmatched character +NumberToken // 5 +PercentageToken // 5% +DimensionToken // 5em +UnicodeRangeToken +IncludeMatchToken // ~= +DashMatchToken // |= +PrefixMatchToken // ^= +SuffixMatchToken // $= +SubstringMatchToken // *= +ColumnToken // || +WhitespaceToken +CDOToken // <!-- +CDCToken // --> +ColonToken +SemicolonToken +CommaToken +BracketToken // ( ) [ ] { }, all bracket tokens use this, Data() can distinguish between the brackets +CommentToken // non-official token +``` + +### Examples +``` go +package main + +import ( + "os" + + "github.com/tdewolff/parse/v2/css" +) + +// Tokenize CSS3 from stdin. +func main() { + l := css.NewLexer(parse.NewInput(os.Stdin)) + for { + tt, text := l.Next() + switch tt { + case css.ErrorToken: + if l.Err() != io.EOF { + fmt.Println("Error on line", l.Line(), ":", l.Err()) + } + return + case css.IdentToken: + fmt.Println("Identifier", string(text)) + case css.NumberToken: + fmt.Println("Number", string(text)) + // ... + } + } +} +``` + +## Parser +### Usage +The following creates a new Parser. +``` go +// true because this is the content of an inline style attribute +p := css.NewParser(parse.NewInput(bytes.NewBufferString("color: red;")), true) +``` + +To iterate over the stylesheet, use: +``` go +for { + gt, _, data := p.Next() + if gt == css.ErrorGrammar { + break + } + // ... +} +``` + +All grammar units returned by `Next`: +``` go +ErrorGrammar +AtRuleGrammar +EndAtRuleGrammar +RulesetGrammar +EndRulesetGrammar +DeclarationGrammar +TokenGrammar +``` + +### Examples +``` go +package main + +import ( + "bytes" + "fmt" + + "github.com/tdewolff/parse/v2/css" +) + +func main() { + // true because this is the content of an inline style attribute + p := css.NewParser(parse.NewInput(bytes.NewBufferString("color: red;")), true) + out := "" + for { + gt, _, data := p.Next() + if gt == css.ErrorGrammar { + break + } else if gt == css.AtRuleGrammar || gt == css.BeginAtRuleGrammar || gt == css.BeginRulesetGrammar || gt == css.DeclarationGrammar { + out += string(data) + if gt == css.DeclarationGrammar { + out += ":" + } + for _, val := range p.Values() { + out += string(val.Data) + } + if gt == css.BeginAtRuleGrammar || gt == css.BeginRulesetGrammar { + out += "{" + } else if gt == css.AtRuleGrammar || gt == css.DeclarationGrammar { + out += ";" + } + } else { + out += string(data) + } + } + fmt.Println(out) +} +``` + +## License +Released under the [MIT license](https://github.com/tdewolff/parse/blob/master/LICENSE.md). + +[1]: http://golang.org/ "Go Language" |