explain_fork_or_die();

Reference

Based on usage it's probably console.log() or var_dump().

At the moment I'm enjoying some JavaScript array methods - filter, map, reduce.

typeof(arg);

surprisingly useful

random() functions, there is so much more behind them then we usually think. I can talk hours about entropy and sources, techniques, pseudo algorithms and how can it improve almost any software product.

$("");

Because it took me almost half a year to realize that it's a function, not a language construct.

Arrow function 🤓. this has never been easier.

mine is fmap ...
fmap :: (a -> b) -> F a -> F b
with F being a Functor :-)

I find this one, truly comforting for some reason.

I like map.put and map.get. Maps/Dictionaries are incredibly useful data structures that we tend to take for granted nowadays.

Don't know if it's only a function, but ajax in Javascript is something else: the whole idea of a function connecting asynchronously to a server and retrieving data without the need of recharge the entire page is amazing.

expect(true).toBe(true);

1. It's a super useful dumb placeholder when just building out describes, its, beforeAlls, etc in Jasmine tests without actually caring about the legit expectations yet.
2. It actually failed for me once, which was... enlightening

map, filter, reduce, forEach, Array.prototype.some, Array.prototype.every

Working with array in Javascript never been easier.
Love it all!

Love throwing exceptions around ;)

throw new Exception("...");
throw Error("...");
raise Exception.Create('...');

In PHP I always include file with my custom helper functions. These two wrap output with <pre/> tags, which allows nice&quick debugging via browser from any class or template code.

function pre($obj = null, $escape = false){
    echo "<pre>";
    if($escape){
        $obj = htmlspecialchars ( print_r($obj, true) );
    }
    print_r($obj);
    echo "</pre>";
}

function dump($obj = null){
    echo "<pre>";
    var_dump($obj);
    echo "</pre>";
}

In Ruby, backticks are a function call. And what's especially cool is that heredocuments with backticks call the same function, but with multi line arguments. So you can define them to do other, more interesting things, like call out to other languages! In practice, I mostly use it when experimenting with some slightly tedious external resource, I basically learned PostgreSQL by running them through these kinds of functions.

require 'open3'

def `(str)
  Open3.capture3('php', stdin_data: str).first
end

<<~`PHP` # => "hello cruel world\n"
hello \
<?php echo "cruel" ?> \
world
PHP

list.zip (other).map ((a,b) =>...)

I don't know why but I just love sprintf() in php ... It's very useful and much more elegant than just endlessly concatenate strings !

And less elegant but really useful once again, die(var_dump()) has a special place in my heart ...

When something went unexpectedly wrong..

panic(error)

reduce is my favorite.

I don't really have a favorite function, because it's all about using the right one to solve a problem. ut I like functions that make things simpler, so I think I'd pick fetch(). Because before, making HTTP requests from JavaScript looked like this

var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
     document.getElementById("demo").innerHTML = this.responseText;
    }
  };
  xhttp.open("GET", "ajax_info.txt", true);
  xhttp.send();

curry function is probably my prefered one.
For those who don't know its utility, here's a basic example:

const divide = curry((a, b) => a / b)
const divide4By = divide(4)

console.log(divide4by(2))
// 2

I even made my own optimized version 😄
npmjs.com/package/super-curry.