Selectors API

A collection of helper functions to get a subset of keys for a set of objects. Typically used by select.

contains

Returns all keys that contain the specified substring.

Parameters

substring

string

The substring that must exist in the keys.

ignoreCase

boolean = true

If true, matches without considering whether letters are upper or lower case (default: true).

Usage

const data = [

{ foo: 1, bar: 20, foobar: 300, FoObAR: 90 },

];

tidy(data, select([contains('oba')]))

// output:

[{ foobar: 300, FoObAR: 90 }]

tidy(data, select([contains('oba', false)]))

// output:

[{ foobar: 300 }]

---

endsWith

Returns all keys that end with the specified substring.

Parameters

suffix

string

The suffix that must exist in the keys.

ignoreCase

boolean = true

If true, matches without considering whether letters are upper or lower case (default: true).

Usage

const data = [

{ foo: 1, bar: 20, foobar: 300, FoObAR: 90 },

];

tidy(data, select([endsWith('bAR')]))

// output:

[{ foobar: 300, FoObAR: 90 }]

tidy(data, select([endsWith('bAR', false)]))

// output:

[{ FoObAR: 90 }]

---

everything

Returns all keys for items in the collection. It is naive and looks only at the first element in the collection.

Usage

const data = [

{ foo: 1, bar: 20, foobar: 300, FoObAR: 90 },

];

tidy(data, select(['foobar', everything(), '-FoObAR']))

// output:

[{ foobar: 300, foo: 1, bar: 20 }]

---

matches

Returns all keys that start with the specified substring.

Parameters

regex

RegExp

The regular expression used to match keys against. You must provide the i flag to have case ignored.

Usage

const data = [

{ foo: 1, bar: 20, foobar: 300, FoObAR: 90 },

];

tidy(data, select([matches(/oba/i)]))

// output:

[{ foobar: 300, FoObAR: 90 }]

tidy(data, select([matches(/oba/)]))

// output:

[{ foobar: 300 }]

negate

Converts the output of any given selector(s) to be prefixed with -, so when combined with select, those keys are dropped.

Parameters

selectors

| string /* keys in the object */

| (items: T[]) => string[] /* selector functions */

| (string | (items: T[]) => string[])[]

Single or array of selector keys or functions.

Usage

const data = [{

date: '2021-01-01',

test_bigint: 123,

test: 12,

foo_bigint: 99,

bar: 13,

}];

tidy(data,

select([negate(endsWith('_bigint')), '-date']))

// output:

[{ test: 12, bar: 13 }]

// same as:

tidy(data,

select(['-test_bigint', '-foo_bigint', '-date']))

---

numRange

Returns all keys that start with the specified substring combined with a numerical suffix within a specified range.

Parameters

prefix

string

The prefix for the keys that will have the numbers appended to.

range

[number, number]

The [min, max] numbers to generate the keys over.

width?

number | undefined

How many leading zeroes the numbers should have, defaults to none.

Usage

const data = [

{ foo07: 1, foo08: 20, foo10: 300, foo11: 90, foo12: 12, bar08: 8, foo: 1 },

];

tidy(data, select([numRange('foo', [8, 11], 2)]))

// output:

[{ foo08: 20, foo10: 300, foo11: 90 }]

---

startsWith

Returns all keys that start with the specified substring.

Parameters

prefix

string

The prefix that must exist in the keys.

ignoreCase

boolean = true

If true, matches without considering whether letters are upper or lower case (default: true).

Usage

const data = [

{ foo: 1, bar: 20, foobar: 300, FoObAR: 90 },

];

tidy(data, select([startsWith('bAR')]))

// output:

[{ foobar: 300, FoObAR: 90 }]

tidy(data, select([startsWith('bAR', false)]))

// output:

[{ FoObAR: 90 }]

---