count

Counts values which satisfy a test.

Alternatives: [count], [countAs].

set.count(x, fn, [ths]);
// x:   a set
// fn:  test function (v, v, x)
// ths: this argument

const set = require('extra-set');

var x = new Set([1, 2, 3, 4, 5]);
set.count(x, v => v % 2 === 1);
// 3

set.count(x, v => v % 2 === 0);
// 2

references

• List-Extra.count: elm
• _.countBy: lodash
• Array.count: sugarjs
• count-iterable-values: @zeke