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Comment by kristopolous | Hacker News Reader

It wouldn't have 200k downloads a week unless there was a large number of programmers who didn't know how to do it.

I mean we're talking FizzBuzz secret sauce here. This must be total black magic for a catastrophic percentage of programmers

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I have not read the source but I had always assumed that this was the lovingly crafted effort of someone who is intimately familiar with the js standard making sure that some hypothetical expression like ![1] is neither odd nor even. Surely the idea that modulo is beyond developers is too horrifying to contemplate.

Sad but true. For JavaScript these kind of functions can actually be useful because of all the quirks. If that was the GPs hint then I can understand.

Here you go:

    /*!
     * is-odd <https://github.com/jonschlinkert/is-odd>
     *
     * Copyright (c) 2015-2017, Jon Schlinkert.
     * Released under the MIT License.
     */
    
    'use strict';
    
    const isNumber = require('is-number');
    
    module.exports = function isOdd(value) {
      const n = Math.abs(value);
      if (!isNumber(n)) {
        throw new TypeError('expected a number');
      }
      if (!Number.isInteger(n)) {
        throw new Error('expected an integer');
      }
      if (!Number.isSafeInteger(n)) {
        throw new Error('value exceeds maximum safe integer');
      }
      return (n % 2) === 1;
    };

It does some checking the `value` is an integer in the safe range, which doesn't even seem right to me. Why shouldn't you be able to call this on integers outside the save range?

All non-safe integers are even, yes?

(10e15 + 1) % 2 === 0

A more catastrophic number of programmers a) dont know how dependencies work and b) think everyone else are idiots.

Perhaps, I solidly understand how dependencies work and in this case my observation is defensible

Someone made the decision to use that and someone thought using stuff made by a person's who makes those kinds of decisions was a good idea and so on.

You can git blame dependencies all the way down and research the parties involved. I've done it, built tools for it even.

A stack of people who make bad decisions doesn't make good software.

More likely the author made another, more useful, package that uses it.

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