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Discussion on: Practical Functional Programming in JavaScript - Control Flow

functional_js profile image
Functional Javascript

I think the problem with your code might be that your second "switchCase" is running with a lamba inside of a lamba, so the actual code you want to test does not get hit.
Correct me if I'm wrong.

Here are my results...
It includes the test of the buggy one.

I ran each "timeInLoop" separately, and about 5 times each, and reported the lowest score.

import { or, switchCase } from "rubico";
import timeInLoop from "./timeInLoop";

const isOdd = x => x % 2 === 1;


//isOdd: 1e+6: 10.013ms
timeInLoop("isOdd", 1e6, () => isOdd(4));

// isOdd_ternary: 1e+6: 9.726ms
timeInLoop("isOdd_ternary", 1e6, () => {
  isOdd(4) ? 1 : 0

// isOdd_ifElse: 1e+6: 9.846ms
timeInLoop("isOdd_ifElse", 1e6, () => {
  if (isOdd(4)) return 'odd'
  else return 'even'

// isOdd_switch: 1e+6: 9.776ms
timeInLoop("isOdd_switch", 1e6, () => {
  switch (isOdd(4)) {
    case true: return 'odd'
    default: return 'even'

//isOdd_rubicoSwitchCase: 1e+6: 152.762ms
timeInLoop("isOdd_rubicoSwitchCase", 1e6, () => {
  switchCase([() => isOdd(4), () => 'odd', () => 'even'])

//@BUG: a nested lambda, the code to be perftested never executes
// isOdd_rubicoSwitchCaseExtraLambda: 1e+6: 10.667ms
timeInLoop("isOdd_rubicoSwitchCaseExtraLambda", 1e6, () => {
  () => switchCase([isOdd, () => 'odd', () => 'even'])
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richytong profile image
Richard Tong Author

I looked into it a bit, turns out the differences we were seeing were due to mocha. I was using it to organize the benchmarks, but I see now that I should probably get closer to the ground. I'll also revise rubico's timeInLoop to model yours more closely.

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functional_js profile image
Functional Javascript

Keep up the good work, and let me know how it progresses and if you come up with more ideas.

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