condition

Advanced condition library for Node, Phantom, RequireJS, CommonJS and the Browser.

Changelog

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Installation

• npm install condition

Usage

Getting an instance of condition can be different depending on the kind of environment you're in. condition supports many different environments and module systems - just try yours, chances are, it'll work. If not, file an issue and I'll work on it.

// Get an instance of condition
var condition = require('condition');

// Wait for a condition to call a function
condition.wait(function() {
    // Do your condition testing here
    return true;
}, function(res) {
    // This is your callback
    // Res is the result from your condition
    console.log('Callback!');
});

// Every time a condition is true, call a function
condition.when(function() {
    // Do your condition testing here
    return true;
}, function(res) {
    // Res is the result from your condition
    return true;
});

// Call a function until a condition becomes true
condition.until(function () {
    // Do your condition testing here
    return true;
}, function (res) {
    // Execute this function until the previous condition returns true
});

Asynchronous Conditions

Sometimes your condition functions will be asynchronous, condition supports that too. Simply ask for at least one argument in your condition function, and condition will assume that it is an asynchronous condition. Call the first argument that the condition function is passed, with your "result", when you're done.

Here's an example:

condition.wait(function (done) {
    setTimeout(function () {
        // Call the done() function you passed as a parameter
        // with the result of your condition
        done("truthy value");
    }, 100);
}, function (res) {
    console.log(res); // logs "truthy value"
});