count
Count value(number, string, array, object...).
Installation
$ npm i --save @cwola/count
require / import
-
esm
import count from '@cwola/count'; -
commonjs
const count = require('@cwola/count');
API
count(val: any, recursive: boolean = false): number
-
Return
Input Return null 0 undefined 0 NaN 0 Infinity 1 Symbol 1 number Math.abs(number) string string.length boolean 1 array, array-like (recursive = false) array.length array, array-like (recursive = true) Count the Number of Key (recursive) object (recursive = false) Object.keys(object).length object (recursive = true) Count the Number of Key (recursive) Countable class class.count() other (e.g. Function) 1
Test
// esm
import count from '@cwola/count';
import assert from 'assert';
assert.equal(0, count(null));
assert.equal(0, count(undefined));
assert.equal(0, count(NaN));
assert.equal(1, count(Infinity));
assert.equal(1, count(Symbol('symbol')));
assert.equal(0, count(0));
assert.equal(3, count(3));
assert.equal(145, count(145));
assert.equal(145, count(-145));
assert.equal(10, count('I\'m cwola.'));
assert.equal(10, count('私はcwolaです。'));
assert.equal(1, count(true));
assert.equal(1, count(false));
assert.equal(1, count(() => {}));
assert.equal(8, count(new Uint8Array(8)));
// countable
class Countable {
count() {
return 5;
}
}
assert.equal(5, count(new Countable));
// array
let o = [1, 2, 3];
assert.equal(3, count(o));
o[99] = 100;
assert.equal(100, count(o));
o = [1, 2, 'I\'m cwola.', new Countable, false, null, undefined];
assert.equal(7, count(o));
// object
o = {a:1, b:2, c:3};
assert.equal(3, count(o));
// recursive
o = [1, 2, 3, [4, 5, [6, 7]], 8, 9];
assert.equal(6, count(o));
assert.equal(11, count(o, true));
o = {a:1, b:2, c:3, d:{e:5, f:[7, 8]}};
assert.equal(4, count(o));
assert.equal(8, count(o, true));