in javascript you can't seed Math.random, if you want something you can seed you have to implement a PRNG yourself
i needed a function that returned a "random" value in [0, 1), like Math.random does, but seedable. importantly, it wasn't for anything even slightly cryptographic or whatever. i had absolutely no requirements for the quality of the output beyond "seems vaguely random to a person"
so here's the simplest, and probably worst (but good enough) PRNG function i found online:
let seed = WHATEVER_NUMBER;
function random() {
const x = seed++/Math.PI;
return x - Math.floor(x);
}
@wallhackio report me you won't
@monorail guess again fucker
@wallhackio do you like my javascript
@monorail it disgusts me
@monorail also, reported a second time for using a function declaration
@wallhackio oh yeah are you supposed to do const random () => {}; now or
@monorail const/let random = function() {} is also good
@wallhackio is function random() {} equivalent to like var random = () => {}; and that's why it's bad or
@monorail function declarations create global variables because javascript sucks
@wallhackio @monorail Global variables, as opposed to what?
You're declaring the function outside of any scope, so what else can it even be except global? Per-file scope like static in C? 
@vaporeon_ @monorail if my web page loaded two javascript files, (lets call them one.js and two.js)
and one.js defines a function
function globalFunc() {
console.log('I am global');
}
then two.js can use that function
wrong
@vaporeon_ @monorail huh i had no idea that c sucks too
re: wrong
@wallhackio @monorail Reported [not actually because I'm a coward] for slandering my favourite programming language
(Also, name a circumstance where you don't want functions to be global?)
re: wrong
@vaporeon_ @monorail in javascript functions can be reassigned
so lets say you work on a web site for your company that uses old-ass ES5 javascript because it was first made in 2009 and its for a government contractor who won't fund what is necessary for your team to change to a newer javascript workflow, so you're stuck with it
In one file, a coworker who no longer works at the company 10 years ago created a function called gorp like so: function gorp() { /* whatever gorp does */}
Now, today you are working on a file that has a function called girp and you reassign it something else. However, you make a typo and write gorp instead. This does not throw at runtime because gorp is global, and now you have bugs that are extremely difficult to decipher because you didn't notice a typo
@wallhackio @monorail Oh!
Functions are global by default in C, too, unless you declare the functions as
static