Introduction
objeq is a simple library that allows POJSO's (Plain-Old JavaScript Objects) to be queried in real-time.
It lets you take a JavaScript Array and query it. Querying includes one or more steps of filtering, drill-down, synthesis, sorting and/or aggregation. It also optionally allows you to generate dynamic results, such that if anything in the original Array changes, the query result will immediately reflect those changes.
Everything else.
The grammar is now frozen but the query engine is still under active development Performance will continue to improve. Note that objeq relies on JavaScript property setters to provide some of its functionality, and so it will only work in more recent browsers and JavaScript environments.
Getting started is so frickin' easy!
A pre-built version of the parser and minified code are already included, but if you'd like to build them yourself and you have node.js, then you can do so by issuing the following command from the package's top-level directory:
> npm install; npm run-script build
This will also install any development dependencies and run the nodeunit test suite.
You can include the objeq Library on your web page with the following HTML:
<script src="objeq.min.js" type="text/javascript"></script>
You can also include the unminified parser and processor with the following:
<script src="objeq/objeq-parser.js" type="text/javascript"></script>
<script src="objeq/objeq.js" type="text/javascript"></script>
Assuming you have installed the objeq Library into your project with npm, you can include it in a node.js module with the following:
var $objeq = require('objeq');
Assuming you have node.js installed, you can fire up the REPL and type the following into the console (minus comments):
// Import the objeq Library
var $objeq = require('objeq');
// Create a data Array to be queried later
var data = [
{ name: 'Barbara', age: 25, gender: 'female' },
{ name: 'Ronald', age: 62, gender: 'male' },
{ name: 'Robert', age: 54, gender: 'male' },
{ name: 'Jessica', age: 48, gender: 'female' }
];
// This will compile an objeq query that filters only those
// Objects having a name property starting with 'Ro' and then
// returns a string that combines name and age properties
var query = $objeq("'^Ro' =~ name -> name + ' is ' + age");
// This performs the query against the 'data' Array and
// returns the result in 'res'
var res = query(data);
// --> res now contains:
// [ 'Ronald is 62 years old',
// 'Robert is 54 years old' ]
If you don't have node.js installed, you can instead open the Query Tester in your browser. It is located in the Examples directory at examples/index.html
For more information about how to interact with the objeq Library and its single API function, see the API Reference at doc/API-Reference.md
For more information about the objeq Query Language itself, including its syntax and grammar, see the Language Reference at doc/Language-Reference.md
This module defines both a Lexer and Grammar that use the Jison Parser Generator (http://zaach.github.com/jison/)