@extra-map/is-value-on v2.0.70

Checks if map has a value. :running: :package:

This is part of package extra-map.

map.isValueOn(x, v, [fn], [ths]);
// x:   a map
// v:   value?
// fn:  map function (v, k, x)
// ths: this argument

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

var x = new Map([['A', 1], ['B', 2], ['C', -3]]);
map.isValueOn(x, 3);
// false

map.isValueOn(x, 3, v => Math.abs(v));
// true