parser-toolkit

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parser-toolkit is a collection of scanner and parser components, which allows fast creation of efficient parser for custom languages. The main point of a toolkit is to support streamable chunked input.

A standard-compiant implementation of JSON is included as a test. This is how JSON is defined:

``js
var ws = {id: "ws", pattern: /\s{1,256}/},
// numeric tokens
nonZero = {id: "nonZero", pattern: /[1-9]/},
exponent = {id: "exponent", pattern: /[eE]/},
numericChunk = {id: "numericChunk", pattern: /\d{1,256}/},
// string tokens
plainChunk = {id: "plainChunk", pattern: /[^\"\\]{1,256}/},
escapedChars = {id: "escapedChars",
pattern: /\\(?:[bfnrt\"\\\/]|u[0-9a-fA-F]{4})/};

var json = new Grammar({
main: [rule("ws"), rule("value")],
ws: repeat(ws),
value: [
any(rule("object"), rule("array"), rule("string"),
rule("number"), ["-", rule("number")],
"true", "false", "null"),
rule("ws")
],
object: [
"{",
rule("ws"),
maybe(rule("pair"),
repeat(",", rule("ws"), rule("pair"))),
"}"
],
pair: [
rule("string"), rule("ws"), ":", rule("ws"), rule("value")
],
array: [
"[",
rule("ws"),
maybe(rule("value"),
repeat(",", rule("ws"), rule("value"))),
"]"
],
string: ["\"", repeat(any(plainChunk, escapedChars)), "\""],
number: [
any("0", [nonZero, repeat(numericChunk)]),
maybe(".", repeat(numericChunk)),
maybe(exponent, maybe(any("-", "+")),
numericChunk, repeat(numericChunk))
]
});
`

The whole definition is taken verbatim from JSON.org.

The test file sample.json` is copied as is from an open source project json-simple under Apache License 2.0.

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