82 lines
1.8 KiB
Markdown
82 lines
1.8 KiB
Markdown
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# JSON [](http://godoc.org/github.com/tdewolff/parse/json) [](http://gocover.io/github.com/tdewolff/parse/json)
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This package is a JSON lexer (ECMA-404) written in [Go][1]. It follows the specification at [JSON](http://json.org/). The lexer takes an io.Reader and converts it into tokens until the EOF.
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## Installation
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Run the following command
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go get github.com/tdewolff/parse/json
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or add the following import and run project with `go get`
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import "github.com/tdewolff/parse/json"
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## Parser
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### Usage
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The following initializes a new Parser with io.Reader `r`:
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``` go
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p := json.NewParser(r)
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```
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To tokenize until EOF an error, use:
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``` go
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for {
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gt, text := p.Next()
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switch gt {
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case json.ErrorGrammar:
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// error or EOF set in p.Err()
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return
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// ...
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}
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}
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```
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All grammars:
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``` go
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ErrorGrammar GrammarType = iota // extra grammar when errors occur
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WhitespaceGrammar // space \t \r \n
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LiteralGrammar // null true false
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NumberGrammar
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StringGrammar
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StartObjectGrammar // {
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EndObjectGrammar // }
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StartArrayGrammar // [
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EndArrayGrammar // ]
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```
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### Examples
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``` go
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package main
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import (
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"os"
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"github.com/tdewolff/parse/json"
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)
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// Tokenize JSON from stdin.
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func main() {
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p := json.NewParser(os.Stdin)
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for {
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gt, text := p.Next()
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switch gt {
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case json.ErrorGrammar:
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if p.Err() != io.EOF {
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fmt.Println("Error on line", p.Line(), ":", p.Err())
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}
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return
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case json.LiteralGrammar:
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fmt.Println("Literal", string(text))
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case json.NumberGrammar:
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fmt.Println("Number", string(text))
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// ...
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}
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}
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}
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```
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## License
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Released under the [MIT license](https://github.com/tdewolff/parse/blob/master/LICENSE.md).
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[1]: http://golang.org/ "Go Language"
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