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What are the great function/method/etc. names in popular libs/languages?

Ben Halpern on July 24, 2018

Naming things is hard, but what are the ones that have stood out to you as great choices that have stood the test of time?

ItsASine (Kayla) • Jul 24 '18

Testing frameworks are fun for this because by nature of what the code does, it ends up being a source of truth for how the app behaves. Thus, the test specs can kind of read like documentation.

Assuming var thing = 10;

Some Jasmine:

expect(thing).toBeTruthy();

expect(thing).not.toBeLessThan(5);

expect(thing).toBeGreaterThanOrEqualTo(5);

expect(thing).toEqual(10);

expect(new Promise(thing)).toEqual(10);

Some Mocha with Chai:

thing.should.be.a('number');

thing.should.equal(10);

expect(thing).to.equal(10);

expect(new Promise(thing)).to.eventually.equal(10);

I also just like the punny names of testing languages, to be honest.

Ben Halpern • Jul 24 '18

Yeah, I find this especially true in Ruby, where whitespace rules can make things almost plain english (though some take this way to far. It's a balance)

Tyler Warnock • Jul 24 '18

I always chuckle at React's componentDidMount vs Vue's mounted

Burdette Lamar • Jul 24 '18

I love Ruby's naming conventions foo? and foo!.

The former is for a method that returns a boolean (like IsFoo in some languages):

irb(main):006:0> s = 'abc'
=> "abc"
irb(main):007:0> s.empty?
=> false

The latter for a method that may do something possibly unexpected, such as modifying a given argument:

irb(main):001:0> s = 'abc'
=> "abc"
irb(main):002:0> s.reverse
=> "cba"
irb(main):003:0> s
=> "abc"
irb(main):004:0> s.reverse!
=> "cba"
irb(main):005:0> s
=> "cba"

Rob Hoelz • Jul 24 '18

Perl's Carp module has some interesting naming choices:

# warn user (from perspective of caller)
carp "string trimmed to 80 chars";

# die of errors (from perspective of caller)
croak "We're outta here!";

# die of errors with stack backtrace
confess "not implemented";

Not to mention that Perl introduces lexical variables with the my keyword, and package variables with the our keyword!

jakebman • Jul 27 '18 • Edited

And those were named to fit the model of die (exit, failing, with message)

Also Perl's or operator is intentionally lower precedence than almost anything else so you can:

my $file = open '/dev/zero' or die "Couldn't open file";

"OR DIE!"

Shalvah • Jul 25 '18

confess 😂😂

Thomas Landin • Jul 24 '18

It's not that the name itself is great, but Python's len() keeps reminding me how well thought-out the early Python language was.

One global function with a short but intuitive name that consistently does exactly what you expect it to no matter what data structure you throw at it.

AoDev • Jul 25 '18

The start of my journey as a programmer is a peculiar one in that regard.

As a non-native English speaker, when I started to code, a long time ago, I simply didn't understand anything. In fact, I thought that most reserved word of any language were just that: some "random strings" with no meaning outside of the programming language. It's later, when I had learned English that I got some Ah ah! moment.

Obviously for an English speaker: "if, case, switch, while, random" are just normal words. It wasn't for me. (I started to play around with code when I was a child, under MS-DOS 6)

So, talking about some great choices, my biggest and relatively recent "Ah ah! moment" has been with

Math.ceil
Math.floor

I could never remember which one would round up and which one would round down.
Until a day like any other day, my brain said: "hey, wait a minute: isn't "floor", because the floor is low and "ceil(ing)" is up?" Awesome. XD

Hugo Di Francesco • Jul 24 '18

unless in Ruby, although it's more of an operator.

Everything in JavaScript (not a fanboy of course), I can't think of a specific method that's named right but I also can't think of any that are named wrong 🤔.

Ben Halpern • Jul 24 '18

Operators are allowed—and anything related to the idea of naming things.

I too really like unless, though I see it get overused sometimes where ! would be clearer.

Eric Curtin • Jul 25 '18 • Edited

"if (!" is clearer to most devs as it is available in more languages than "unless".

kip • Jul 24 '18

A common problem in PHP (maybe in some other langs too) is the way to move between dates and get the incorrect value, for example when you decrease or increase a month(s):

>>> (new \DateTime('2017-01-31'))->add(new \DateInterval('P1M'))->format('Y-m-d')
=> "2017-03-03"

Carbon a good library offers some methods to avoid this behaivor and their names are really good:

>>> (new Carbon('2017-01-31'))->addMonthNoOverflow()->format('Y-m-d')
=> "2017-02-28"

If you wanna get the calculation with this behaivor, no problem:

>>> (new Carbon('2017-01-31'))->addMonthWithOverflow()->format('Y-m-d')
=> "2017-03-03"

Other methods are: createMidnightDate, localeHasDiffOneDayWords, createSafe...

Javier Garcia • Jul 24 '18

.NET's FirstOrDefault() method when accessing LINQ. I find it super clear :)

Chad Smith • Jul 25 '18

Now only if I could convince people to quit thinking FirstOrDefault will always return null if it can't find anything.

It does what it says it does, default value. It just so happens that for objects that is null
(I say this because I had to prove to someone once that their if statement would always evaluate to true. Lol)

Ben Halpern • Jul 24 '18

Less clear along those lines is the ||= operator.

What does ||= do?

Alex

#explainlikeimfive#ruby

robencom • Jul 24 '18

Hey, PHP has the coolest operator: the SPACESHIP operator <=>

kip • Jul 24 '18

The <=> is for evaluation and ||= is for assigment, the ?? null coalescing operator is more close to it but are not the same.

Nimmo • Jul 24 '18

Maybe in Elm, not only because it's descriptive (Maybe it has a value, and Maybe it doesn't), but when it doesn't have a value, instead of null or undefined or whatever, it's Nothing.

Which makes me think of Nathan Explosion whenever I use it.

youtube.com/watch?v=o_PMab-SGgY

Galdin Raphael • Jul 28 '18

Android's UserManager class has something called isUserAGoat().

Here's an interesting discussion on it 😁
stackoverflow.com/questions/133753...

Ben Klein • Jul 25 '18 • Edited

I really like the convention to name mixins with-something in react and Vue. Often this feels very elegant. Like with-captcha.js or with-user.js. There couldn't be any naming that feels any smoother 😍

Paweł Świątkowski • Jul 26 '18

Not sure if this counts, but PHP's T_PAAMAYIM_NEKUDOTAYIM parser token is pretty rad yet savage :D

Omar Alshaker • Aug 4 '18

I really like PHP's explode and implode couple. It's String.split and String.join for those who don't know.

George • Jul 25 '18

From one of my most recent projects

void iDontKnowIfThisIsGoingToWorkSoImPuttingOffUsingThisMethodBecauseImScaredOfTheOutcome()

Paweł Świątkowski • Jul 26 '18

Damn, I was going to post this when I saw this thread ;)

Ben Halpern • Jul 24 '18 • Edited

I thought to make this thread based on a conversation I was having in @aspittel 's great clean coding post.

Ben Halpern

Jul 23

I love React's dangerouslySetInnerHTML which replaces a lot of documentation and comments and forces the user to understand what's going on. If you don't know why it says "dangerous", you can look it up.

Much better than

//This is dangerous, read this post about XSS:
setInnerHTML

Because the comment would never get ported across all the use cases (obviously, given it's a library).

But most code doesn't live up to the scrutiny of library code and comments, used properly, are a perfectly reasonable part of the toolbelt.

Jesse Ditson • Jul 28 '18

I always thought it was kind of brilliant of the react team to hijack the reader’s brain to create a fake protected member by naming it _SECRET_DOM_DO_NOT_USE_OR_YOU_WILL_BE_FIRED

Ben Halpern • Jul 28 '18

Functional propaganda