f-validators

Toolkit of validation functions easy to compose into bigger validators.

Installation

npm i -S f-validator

Usage

const validators = require('f-validators');

Simple Validation

validators.isEqual(true, true) // => true;

validators.isInstanceOf(Date, 5) // => false;

validators.isOk(true) // => true;

Validator Composition

f-validators provides the functions and, or and not to easily compose validators into bigger and more precise ones.

const {or, not, isNull, isUndefined} = require('f-validators');
const isNotNull = not(isNull);
const isNotUndefined = not(isUndefined);
const isNotNullOrUndefined = or(isNotNull, isNotUndefined);

const isNotNullOrUndefined(null) // => false
const isNotNullOrUndefined(undefined) // => false
const isNotNullOrUndefined(42) // => true

Partial Validators

Validators are handy when combined with partial functions for evaluating the same condition continuously.

const is5000 => (comparable) => isEqual(comparable, 5000);

is5000(200) // => false
is5000(5000) // => true

Object Validation

Stack your validations to easily build object validation.

const validateFieldA = ({ a }) => isNumber(a);
const validateFieldB = ({ b }) => isString(b);

const myObectValidator = and(validateFieldA, validateFieldB);

myObectValidator({a: 5, b: '5'}) // =>  true;
myObectValidator({a: 5, b: true}) // =>  false;

Functions

Whole lotta them!

or

Returns a function that passes an argument to all given functions. Will only return false if all functions return false.

or(...functions) => function

const isStringOrNumber = or(isString, isNumber)
isStringOrNumber(123) // => true,
isStringOrNumber('123') // => true,
isStringOrNumber(true) // => false,

not

Returns a function that reverts the result of a given function.

not(fn) => function

const is5 = v => isEqual(5, v);
const isNot5 = not(is5);
isNot5(5) //=> false

and

Returns a function that reverts the result of a given function.

and(...fn) => functions

const hasLengthOf5 = v => hasLengthOf(5, v);
const isStringAndHasLengthOf5 = and(isString, hasLengthOf5);
isStringAndHasLengthOf5('12345') // => true

isEqual

Simple comparison of two objects using the === operator.

isEqual(first, second) => boolean

isEqual(5, 3) // => false

isInstanceOf

Instance check using the instanceof operator.

isInstanceOf(constructor, instance) => boolean

const date = new Date();
isInstanceOf(Date, date) // => true

pending for docs...

isMatch(expression, string) isOk(truthy) isTypeOf(type, object) isUndefined(object) isNull(object) hasLengthOf(iterable, length) isString(string) isNumber(number) isBoolean(boolean) isObject(object) isDate(date)