js-value-parser

deserialize javascript objects including non-standard JSON in fragmented text

Installation

npm install js-value-parser

Useage

parse(msg, [offset, [options]])

parse(ast, [options])

example:

const {
  parse,
  FILTER_JSONP,
} = require('js-value-parser');
 
const msg = '... xxx = {a:1} ... ';
console.log(parse(msg, msg.indexOf('=') + 1)); // => { a : 1 }
 
console.log(parse('jsonpCallback([2])', 0, {filter: FILTER_JSONP})); // => [2]

options

context - the value map of identifier refers, default CONTEXT_MINIMUM

filter - find the target ast node, default FILTER_LEFTEST

evaluator - calculate ast's values, default EVALUATOR_CONSTANT

Components

• context

  • CONTEXT_MINIMUM: only include undefined, Infinity, NaN

• filter

  • FILTER_LEFTEST: find the ast node of object or constant on the left side
  • FILTER_JSONP: find the ast node of the first argument of function calling

• evaluator

  • EVALUATOR_CONSTANT: turn !0,!1,void 0 into true,false,undefined, then statically evaluating constant value (object, array, string, number, boolean, null & refers in context), otherwise throw an error (e.g. invoke function)