A type checking utility for element(s) of an Array based on chaining flow to combine multiple operations.

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🚀 Installation

NPM

$ npm install @akanshgulati/are  

YARN

$ yarn add @akanshgulati/are  

🎉 Usage

const Are = require('@akanshgulati/are');  
  
Are([1,2,3,4]).of.number();  
//=> true  
  
Are(["🎉","🎁","🔆" ]).of.type('string');  
//=> true'  
  
Are(["a", "b", "c"]).of.not.type('string');  
//=> false  
  
Are([[[[[[[[[1]]]]]]]]]).flat.of.number();  
//=> true  

📙 API

Helpers

Helps in selected a particular set of an array and negative of the current type-check

.all - checks for all elements (default)  
.any - checks for all elements of array  
.first - check for first element  
.last - check for last element  
.middle - check for middle element(s)
.flat - check for type in flatten array
.not - checks for opposite, e.g. (.not.any => .all)  

Types

.type(<value>)

The value needs to be in Pascal case (e.g. NaturalNumbers) or Underscore separated (e.g. natural_number)

Primitive types

String
Number
Object
Array
Boolean
Date
ArrayBuffer

Array types

Int8Array
Uint8Array  
Uint8ClampedArray  
Int16Array  
Uint16Array  
Int32Array  
Uint32Array  
Float32Array  
Float64Array  
BigInt64Array  
BigUint64Array  
ArrayBuffer  
SharedArrayBuffer  
DataView

Number types

Integer  
SafeInteger  
Decimal  
Float  
Finite  
Infinite  
NaturalNumber  
WholeNumber  
PositiveNumber  
NegativeNumber  
Zero  

Boolean types

Falsy  
Truthy

Built-in methods

.string()

.number()

.array()

.boolean()

.null()

.undefined()

.date()

.int8Array()

.uint8Array()

.uint8ClampedArray()

.int16Array()

.uint16Array()

.int32Array()

.uint32Array()

.float32Array()

.float64Array()

.bigInt64Array()

.bigUint64Array()

.dateView()

.arrayBuffer()

.sharedArrayBuffer()

.integer()

.safeInteger()

.finite()

.infinite()

.wholeNumber()

.positiveNumber()

.negativeNumber()

.zero()

.decimal()

.float()

.truthy()

.falsy()

Check all elements (default)

• Are(ARRAY).of.type(value) // custom('string', 'number', 'object', 'boolean', 'array')
• Are(ARRAY).of.number() or Are(ARRAY).of.number() or Are(ARRAY).all.of.number()
• Are(ARRAY).of.object() or - Are(ARRAY).of.object() or - Are(ARRAY).all.of.object()
• Are(ARRAY).of.string() or - Are(ARRAY).of.string() or - Are(ARRAY).all.of.string()
• Are(ARRAY).of.boolean() or - Are(ARRAY).of.boolean() or - Are(ARRAY).all.of.boolean()

Check one element

• Are(ARRAY).any.of.type(value) // custom('string', 'number', 'object', 'boolean', 'array')
• Are(ARRAY).any.of.number()
• Are(ARRAY).any.of.object()
• Are(ARRAY).any.of.string()
• Are(ARRAY).any.of.boolean()

Check at particular index

• Are(ARRAY).middle.of.type(value) // checks for (n-1)/2 index in case of odd and (n-1)/2 and n/2 indexes in case even
• Are(ARRAY).first.of.type(value) // checks for 0th index for type value
• Are(ARRAY).last.of.type(value) // checks last element for type value
• Are(ARRAY).middle.of.not.type(value) // returns true if neither of middle index(s) is of a type value
• Are(ARRAY).first.of.not.type(value) // checks only for 0th index for not to be of type value

Check in nested array

• Are(ARRAY).flat.of.type(value) // flatten array to same root and then checks for all elements for type value

Negation

• Are(ARRAY).of.not.type(value) // checks if all the elements are of not type value

🍺 Inspiration

No package available online which checks for an array of elements

1. It checks not only for a single element, instead, checks for an array of data
2. Chaining technique to add multiple operations in one go
3. Performant while type checking an array of elements.
4. Provides selection helpers for type checking a particular element of an array
5. Supports negation for checking opposite to current type checking.

🗜️ Examples

You can refer to test file for various examples on above types, see examples.

🔗 Related

Currently there are multiple libraries which check for a single element but not for an array of elements.

• is - Package which checks single element
• expect - Chaining of operations for testing assertions
• @sindresorhus/is - Advanced type checking of over 100 types.

✔️ To-do

• Check for an empty array isEmpty()
• Add support for TypeScript type gaurds
• More type checking like .int16Array(), .float32Array()
• Check for truthy elements if no element is undefined or null, .isTruthy()
• Check for integers, float values under type number, 'integers(), decimals()

👨‍💻 Maintainers

• Akansh Gulati