fjl-mutable

Functional and "typed" defineProp, defineEnumProp, defineProps, defineEnumProps functionality.

Sections in Readme:

• Requirements
• Getting Started
• Docs
• Motivation
• Development
• Supported Platforms
• License
• Resources
• Change log

Requirements:

• Javascript Ecmascript 5+.

Supported Platforms:

Browsers

• IE9+, and all other modern day browsers.

NodeJs

• 8+

Getting Started:

In NodeJs:

Using es2015 modules:

import {...} from 'fjl-mutable';

Using CommonJs modules:

const {...} = require('fjl-mutable');

In Browser:

See desired export type below:

• './dist/amd/' - Asynchronous module format.
• './dist/cjs/' - CommonJs module format.
• './dist/umd/' - Universal module definition format.
• './dist/iife/' - Immediately Invoked Function Execution - (exports fjlMutable as a global).
• './dist/es6-module/' - Ecmascript 6 module format.

Docs

JSDocs are here (https://functional-jslib.github.io/fjl-mutable/) [https://functional-jslib.github.io/fjl-mutable/].

fjlMutable methods

createTypedDescriptor, toEnumerableDescriptor, toTargetDescriptorTuple,
defineProp, defineEnumProp, defineEnumProps, defineProps

In-line summary docs follow:

defineProp(TypeRef, propName, targetOrTargetTuple, defaultValue = undefined) : Descriptor

Defines a property on target that is constricted to given Type (TypeRef). HaskellType: defineProp :: TypeRef -> String -> TargetOrTargetTuple -> Any -> Descriptor

defineEnumProp(TypeRef, propName, targetOrTargetTuple, defaultValue = undefined) : Descriptor

Defines an enumerable property on target that is constricted to given Type (TypeRef). HaskellType: defineEnumProp :: TypeRef -> String -> TargetOrTargetTuple -> Any -> Descriptor

const someDefaultValue = 
class User {
    static defaultRole = 'guest';
    constructor ({firstName, age}) {
        defineEnumProp(String, 'firstName', this, firstName); // if `firstName` here is not of type `String`, detailed error thrown  
        defineEnumProp(Number, 'age', this);
        defineEnumProp(String, 'role', this, User.defaultRole);
        this.age = age; // This is fine since our setter expects a number
        this.age = 'hello world'; // This throws a detailed error ('`#User.age` 
                                  //   ... expects type: "Number" ... Type received ...' etc.
                                  // )
    }
}

// Later..
const user = new User();
user.firstName = "Some name";
user.age = '99'; // Throws (detailed) error since type does not match.

defineEnumProps(argTuples, target) : Array<Array<Target, Descriptor>>

Defines enumerable properties all at once on specified target.

Params:

• argTuples {Array} - Array of argument lists of the same type that defineEnumProps takes: E.g., Array.<TypeRef, String, TargetOrTargetTuple, Any> with one distinction: 3rd argument is optional (target argument).

const someTarget = {};
defineEnumProps([
    [String, 'someProp', someDefaultValue],
    [String, 'someProp2', someDefaultValue2],
    [String, 'someProp3', someTarget, someDefaultValue3],
    [String, 'someProp4', [someTarget, somePropDescriptor], someDefaultValue4],
], someTarget);

• target {*} - Target to define properties on.

Example usage:

const someDefaultValue = 'someValueHere';
class User {
    static defaultRole = 'guest';
    constructor ({firstName, age}) {
        defineEnumProps([
            [String, 'firstName', firstName],   // if `firstName` here is not of 
                                                // type `String`, detailed error thrown
            [Number, 'age'],
            [String, 'role', User.defaultRole]
        ], target);
        this.age = age;                         // This is fine since our setter expects a number
        this.age = 'hello world';               // This throws a detailed error ('`#User.age` 
                                                //   ... expects type: "Number" ... Type received ...' etc.
                                                // )
    }
}

// Later..
const user = new User();
user.firstName = "Some name";
user.age = '99'; // Throws (detailed) error since type does not match.

defineProps(argTuples, target) : Array<Array<Target, Descriptor>>

Same as defineEnumProps though doesn't make props enumerable on target. See params description and examples below:

Params:

• argTuples {Array} - Array of argument lists of the same type that defineEnumProps takes: E.g., Array.<TypeRef, String, TargetOrTargetTuple, Any> with one distinction: 3rd argument is optional (target argument).

const someTarget = {};
defineEnumProps([
    [String, 'someProp', someDefaultValue],
    [String, 'someProp2', someDefaultValue2],
    [String, 'someProp3', someTarget, someDefaultValue3],
    [String, 'someProp4', [someTarget, somePropDescriptor], someDefaultValue4],
], someTarget);

• target {*} - Target to define properties on.

Example usage:

const someDefaultValue = 'someValueHere';
class User {
    static defaultRole = 'guest';
    constructor ({firstName, age}) {
        defineProps([
            [String, 'firstName', firstName],   // if `firstName` here is not of 
                                                // type `String`, detailed error thrown
            [Number, 'age'],
            [String, 'role', User.defaultRole]
        ], target);
        this.age = age;                         // This is fine since our setter expects a number
        this.age = 'hello world';               // This throws a detailed error ('`#User.age` 
                                                //   ... expects type: "Number" ... Type received ...' etc.
                                                // )
    }
}

// Later..
const user = new User();
user.firstName = "Some name";
user.age = '99'; // Throws (detailed) error since type does not match.

Development:

• For commands see './package.json' scripts.

Dir structure

• Everything is in './src'.
• Distribution is in './dist'.
• Docs are in './docs'.

Testing

Using jest (see './package.json' scripts).

License:

BSD 3 Clause - Included in sources.

Resources:

• defineProperty - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperty
• defineProperties - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/defineProperties
• Data Types - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Data_structures

Change log

0.18.0

Breaking changes

• Removed uncurried methods (methods ending with $) (use curried methods instead). Removed:

• errorIfNotTypeOnTarget$ - ('fjl' provides this now)

• errorIfNotTypeOnTarget - ("")

• defineEnumProps$

• defineProps$

• Renamed auxillary methods:

  • _descriptorForSettable becomes createTypedDescriptor.
  • _makeDescriptorEnumerable becomes toEnumerableDescriptor.
  • _targetDescriptorTuple becomes toTargetDescriptorTuple.

Other changes:

• Normalized API (removed un-curried methods from exports and non-api specific (un-required) methods).
• Updated build process (using babel7 now).
• Replaced mocha and chai with jest.
• Changed license from "MIT" to "BSD3".
• Version and build tag links to top of readme file.
• Et. al.