Allege

Make complex conditionals easier to read and write.

Introduction

Sometimes, if statements can get very complex. For example:

if (foo.bar === 'value_a' || foo.bar === 'value_b' || foo.bar === 'value_c' || foo.bar === 'value_d' || foo.bar === 'value_e') {
    // do something
}

With Allege, you can simplify your if like so:

if (allege.that(foo.bar).isIn(
    'value_a', 
    'value_b', 
    'value_c', 
    'value_d',
    'value_e'
)) {
    // do something
}

API & Methods

Allege exposes different functions based on what you're trying to compare.

Single Input Commands

To use these methods, call allege.that() with just a single argument, like so: allege.that(foo). Then, these methods will be available:

isIn(possibility1, ..., possibilityN) -> boolean

Determines whether foo is referentially equal (===) to any of the possibility items.

allege.that(5).isIn(1, 2, 3, 4, 5, 6);
// --> true

allege.that('hi').isIn('hello', 'good morning', 'sup');
// --> false

isNotIn(possibility1, ..., possibilityN) -> boolean

Determines whether foo is referentially unequal (!==) to all of the possibility items.

allege.that(5).isNotIn(1, 2, 3, 4);
// --> true

allege.that(5).isNotIn(1, 2, 3, 4, 5);
// --> false

Multiple Input Commands

To use these methods, call allege.these() with more than one argument, like so: allege.these(foo, bar, baz, quux). Then, these methods will be available:

areAll(possibility) -> boolean

Determines whether all inputs are referentially equal (===) to the possibility item.

allege.these(5, 5, 5, 5).areAll(5);
// --> true

allege.these(5, 4, 5, 4).areAll(4);
// --> false

areAllNot(possibility) -> boolean

Determines whether all inputs are referentially unequal (!==) to the possibility item.

allege.these(5, 5, 5, 5).areAllNot(4);
// --> true

allege.these(5, 5, 5, 5).areAllNot(5);
// --> false

Installation

Grab this module from npm with the following command:

yarn add allege

Then you can use it in your project like so:

import allege from 'allege';
if (allege.that(5).isNotIn(1,2,3)) {
    // do something
}

// or:
import { that, these } from 'allege';
if (that(5).isNotIn(1,2,3)) {
    // do something
}

Versioning

This module follows SemVer.

License

MIT. See the LICENSE file for more details.

Testing

You can execute the existing test suite by running the following in your terminal:

yarn install
yarn test

Building From Source

The code that resides in the index.js file is transpiled from an ES6 source. The original source files reside in the src/ directory. These can be built with the following command:

yarn build