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Check if a number is equal to 13.

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An npm package to check if a number is equal to 13.


npm --save i is-thirteen


yarn add is-thirteen


const isThirteen = require('is-thirteen');

// PLEAS READ THE SOURCE CODE BECAuse we moved fast and broke things

i̶s̶T̶h̶i̶r̶t̶e̶e̶n̶(̶2̶5̶)̶;̶ ̶/̶/̶ ̶f̶a̶l̶s̶e̶ i̶s̶T̶h̶i̶r̶t̶e̶e̶n̶(̶1̶3̶)̶;̶ ̶/̶/̶ ̶t̶r̶u̶e̶

const is = require('is-thirteen');
// Now with elegant syntax.

is(13).thirteen(); // true is(12.8).roughly.thirteen(); // true is(6).within(10).of.thirteen(); // true is(2008).yearOfBirth(); // true

// check your math skillz is(4).plus(5).thirteen(); // false is(12).plus(1).thirteen(); // true is(4).minus(12).thirteen(); // false is(14).minus(1).thirteen(); // true is(1).times(8).thirteen(); // false is(26).divideby(2).thirteen(); // true


npm test



A helpful tool by Jezen Thomas with helpful help from Gytis Daujotas and many fine folk.

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