simple-overloading v1.0.0

simple-overloading

Simple function overloading for node.js

Install

npm install -g simple-overloading

Usage

Simple example

var SOverloading = require('../');

function myFn() {

    //-- this is your variable scope with its default values

    var scope = {
        full_name       : '',
        send_sms        : true
    };


    /**
     * this is your first method variation:
     * myFn( {String} full_name [ = '' ] );
     */

    var m1 = {
        'full_name'     : 'string'
    };

    /**
     * this is your second method variation:
     * myFn( {String} full_name [ = '' ] , {Boolean} send_sms [ = true ] );
     */

    var m2 = SOverloading.extendMethod(m1,{
        'send_sms'      : 'boolean'
    });

    if (!SOverloading.variation([m1,m2],scope,arguments)) {
        throw new Error('Method not found...');
    }

    console.log(scope);
}

myFn('Martín Rafael González');
/* { full_name: 'Martín Rafael González', send_sms: true } */

myFn('Martín Rafael González',false);
/* { full_name: 'Martín Rafael González', send_sms: false } */

myFn( { full_name : 'Martín Rafael González' } );
/* { full_name: 'Martín Rafael González', send_sms: true } */

myFn('Martín Rafael González','hello');
// throws error

When we add our method variations, we can set the type and even the values we want to use.

var m1 = {
    full_name       : 'string', // only accept strings
    phone_number    : 'string,number', // accept strings or numbers
    sex             : 'string:male,female', // accept only strings with value 'male' or 'female',
    additional      : '^function' // accepts any value but a function
};

Allowed value types

• string: matches any string
• array: matches only arrays (not objects...)
• object: matches only objects (not arrays)
• number: matches 10, 10.1, '10', '10.4'
• integer: matches '786' or 786 but not 10.1 or '10.5'
• boolean: matches '1', '0', 1, 0, true or false
• function matches only functions

You can use the modifier ^ at the beginning of any type in order to match anything but that type. For example ^string matches any type of value but strings.

You can also define some accepted values. For example, if you want to allow only female or male on a gender field, use: { gender : 'string:male,female' }

Advanced usage

var SOverloading = require('simple-overloading');
function myFn() {

    //-- let's first define our scope with its default values

    var scope = {
        full_name       : '',
        sex             : '',
        phone_number    : null,
        send_sms        : true,
        callback        : null
    };


    //-- later we define our method variations

    //myFn({String} full_name, {String} sex[ = male | female ])
    var m1 = {
        full_name       : 'string',
        sex             : 'string:male,female'
    };

    //myFn({String} full_name, {String} sex[ = male | female ], {Number} phone_number)
    var m2 = SOverloading.extendMethod(m1,{
        phone_number    : 'integer'
    });

    //myFn({String} full_name, {String} sex[ = male | female ], {Function} callback)
    var m3 = SOverloading.extendMethod(m1,{
        callback        : 'function'
    });

    //myFn({String} full_name, {String} sex[ = male | female ], {Number} phone_number, {Function} callback)
    var m4 = SOverloading.extendMethod(m2,{
        callback        : 'function'
    });


    /**
     * 0 => didn't match any method
     * > 0 && <= SOverloading => method matched
     * > SOverloading => scope provided by object
     */

    var methodFound = SOverloading.variation([m1,m2,m3,m4],scope,arguments);

    if (methodFound < 1) {

        throw new Error('Method not found!');

    }

    console.log('Matched with method ',methodFound);

    console.log(scope);

    scope.callback && scope.callback(scope);

}

function mycb() {

    console.log('do whatever!');

}

myFn('Martín Rafael González','male');

/**
{ full_name: 'Martín Rafael González',
  sex: 'male',
  phone_number: null,
  send_sms: true,
  callback: null }
*/

myFn('Ana Sosa','female',40404040);

/**
{ full_name: 'Ana Sosa',
  sex: 'female',
  phone_number: 40404040,
  send_sms: true,
  callback: null }
*/

myFn('Rafael Cotiz','male','4442555510',mycb);

/**
{ full_name: 'Rafael Cotiz',
  sex: 'male',
  phone_number: 4442555510,
  send_sms: true,
  callback: [Function: mycb] }
*/

myFn('Olivia Gonzalez','feminine'); //throws error: method not foud...