npm install olsen


Two of a kind check
npm i olsen
In general, olsen(x, y)(func) ≡ func(x) === func(y).
``js
var olsen = require('olsen');
olsen(1, 3)(isEven); // => true, both of kind "not even"
olsen(2, 4)(isEven); // => true, both of kind "even"
olsen(1, '1')(Number); // => true
olsen(1, 0.99999999999999999)(Number); // => true, 0.999... becomes exactly 1
olsen(1, 0.9999999999999999)(Number); // => false
olsen(0, 2 * Math.PI)(Math.cos); // => true
olsen(NaN, NaN)(function(x) {
return x;
}); // => false, NaN !== NaN
``
See use case and accompanying tests.