Bootstrap's maintainer hates the semicolon

https://github.com/twitter/bootstrap/issues/search?q=semicolon

by wyuenho • 14 years ago

173 133 14 years ago

github.com

jondot• 14 years ago

That's a reasonable thing to hate.

nestlequ1k• 14 years ago

If you're going to use JS, you're not allowed to change things like this. It just causes problems for people.

Easy solution, use CoffeeScript and have it compile down to JS. My favorite feature of CoffeeScript is the ruby/python line conventions spacing (2 spaces, no tabs), and no semicolons.

They're already compiling the CSS from Less. Seems natural to add CoffeeScript to the chain.

lloeki• 14 years ago

For the sake of completeness, PEP8 actually says 'Use 4 spaces per indentation level'

mrspeaker2• 14 years ago

He's not changing anything, and he's not relying on weird browser implementations - it's part of the spec.

I hate unnecessary semicolons too. Though I deal with them by including them everywhere, but making them hard to see in my editor ;)

VMG2• 14 years ago

alternatively, use JSLint

beaumartinez• 14 years ago

I much prefer JSHint. JSLint is draconian, and has some borderline insane decisions (it complains if you don't declare your vars at the top of a block—is this 1980?).

And yes, I realise that some of these options can be turned off—but JSHint has better defaults.

Rajiv_N4• 14 years ago

Thanks for drawing my attention to this. Currently, I maintain a separate branch simply for adding the missing semicolons so that I can link the individual bootstrap files with my project. It's been quite annoying and I now know that the annoyance may not go away anytime soon.

I hate these ideologues. But this is the trouble with JS I guess. I actually love javascript because of the highly dynamic nature of it. But that dynamism also lends itself to these kind of problems. I don't know of any other language where people can CHOOSE to follow syntax. Part of the problem is the awkward interpreter specs I guess. But also, with JS seems like everyone has an opinion :)

willvarfar• 14 years ago

Your branch can become the new public useful one perhaps?

Rajiv_N4• 14 years ago

Yeah, I've been thinking about doing this. I was kinda hoping that the missing semicolons were just an oversight on the bootstrap teams part.

Now that I know there is some demand for a branch of this sort, I'll share it ASAP.

EDIT: the repo is at https://github.com/rajivnavada/bootstrap

oscardelben• 14 years ago

You can do it in Ruby and lots of other languages

TomasSedovic• 14 years ago

Ruby, Python, Go, JavaScript, Bash, even Clojure -- kinda.

https://gist.github.com/1815639

Of course, unless you're the sole writer and reader of the code, it's generally good to follow the common practices that evolved around the particular language.

freshhawk• 14 years ago

Relying on multiple different parser's implementation of the "auto semicolon insertion guesser" feature seems insane to me.

I'm a python/haskell guy too, I hate semicolons. But I'll put up with them because javascript needs them, it doesn't enforce them, but to write sane, maintainable code it really needs them.

Javascript is enough of a mess, this kind of thing just throws gas on the fire.

Have you published your branch? I think it would be very useful.

spicyj• 14 years ago

JavaScript doesn't need them any more than Python does; they're used almost always simply because people don't know the (simple) rules of when statements end.

rplnt• 14 years ago

You can use semicolons in python. You have to use them if you want multiple statements in one line..

Tichy2• 14 years ago

Adding semicolons is also an ideology.

Deestan• 14 years ago

> I don't know of any other language where people can CHOOSE to follow syntax.

Your argument is incorrect. :) Omitting semicolons is perfectly valid and correct syntax. The spec is explicit about it being allowed and how the code shall be interpreted: http://es5.github.com/

It may be a good rule of thumb to use the semicolons, because you have to be careful without them, but in the end it's a choice based on team preference. If you are a very pertinent and careful type of person, and you don't have any rabid illiterates on your team, going without semicolons makes perfect sense.

Rajiv_N4• 14 years ago

The spec has provisions for automatic semicolon insertion that need to be considered carefully before deciding to completely ignore them. Now consider that http://twitter.github.com/bootstrap/index.html says the following:

"Bootstrap is designed to help people of all skill level—designer or developer, huge nerd or early beginner. Use it as a complete kit or use to start something more complex."

So: 1. "illiterates" are welcome to use it. 2. If the goals are to be met, do not assume anything that can be interpreted differently by different players.

zbuc• 14 years ago

> If you are a very pertinent and careful type of person, and you don't have any rabid illiterates on your team, going without semicolons makes perfect sense.

Why does it make perfect sense? There's nothing wrong with including them, and I find it reduces the amount of thinking you need to do. JavaScript has C-like syntax; it should end its lines with semicolons and it's a mistake that it doesn't always require them.

maaku• 14 years ago

> I don't know of any other language where people can CHOOSE to follow syntax.

You should check out Lisp macros ;)

latchkey• 14 years ago

I don't get what the issue is. I run bootstrap js through the closure compiler (with minification and optimization) and it works just fine. I don't agree with the policy myself, I prefer semicolon, but I also prefer CoffeeScript. That said, if Fat wants to remove it, that is his choice, leave him alone. Update: Just read his blog posting. If Fat really wanted the minimalist approach, he'd use coffeescript and then people would bug him over that choice instead. ;-)

dasil003• 14 years ago

Did you just say using CS is minimalist?

danneu• 14 years ago

I believe he was referring to terse code.

slantyyz• 14 years ago

I don't get what the issue is either. Are we forgetting that Bootstrap is free and open source?

Nobody's forcing anyone to use Bootstrap nor is anyone prevented from creating their own Bootstrap fork with semicolons.

Clearly, no good deed goes unpunished.

Tichy2• 14 years ago

huh, isn't the bug rather in the software that can't deal with the "missing" semicolons? (I hate semicolons, too)

secoif• 14 years ago

I agree with this, any minifier worth using handles semicolons just fine. Try uglify.

evan_3• 14 years ago

He wrote a blog post about this a while ago, I don't really get his reasoning but I guess he's happy with his decisions:

http://www.wordsbyf.at/2011/10/31/i-dont-write-javascript/

damncabbage2• 14 years ago

And possibly some reasons why leaving semicolons off can make his or others' lives a bit annoying:

http://bonsaiden.github.com/JavaScript-Garden/#core.semicolo...

ricardobeat15• 14 years ago

That's a part of JS Garden I don't agree with. Leaving semi-colons only changes behaviour if your code is wrong in the first place...

idan• 14 years ago

This blog post accurately states the broken idea:

> Each is perfectly valid. Each behaves the same. It’s just a matter of preference and finding the style that makes most sense to you.

Part of being a good steward to a successful project is realizing that writing code for yourself is a Bad Idea™. If thousands of people are using your code, then write your code for maximum clarity, not your personal preference of how to get clever within the spec.

Code is harder to read than to write. To borrow a line from Jacob Kaplan-Moss, if I write the cleverest code that I am able to, then by definition I won't be able to understand it later.

This semicolon approach isn't invalid, but it is clearly a source of confusion, and it requires that users comprehend the choice and the tradeoffs. This seems like a poor choice for a framework whose audience is largely people who don't grok this stuff and are bolting it on wholesale.

<3 bootstrap, just my $0.02.

dominicrodger• 14 years ago

The quote is Kernighan's I think: "Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it."

nahname• 14 years ago

It is a valuable and documented code quality. http://en.wikipedia.org/wiki/Principle_of_least_astonishment

Principle of least astonishment (POLA) was also a core design decision behind ruby. http://en.wikipedia.org/wiki/Ruby_(programming_language)#Phi...

ricardobeat15• 14 years ago

Leaving semi-colons out is not clever, it's just understanding where you need them instead of shooting blindly.

po• 14 years ago

This one bit me the other day and forced me to switch JavaScript compressors because the one I was using (it was python-based) didn't get the IIFE (http://benalman.com/news/2010/11/immediately-invoked-functio...) right when appending files together.

In this blog posting Jacob writes:

The majority of lines however don’t end with semicolons because they simply aren’t necessary and I prefer the minimalist aesthetic. For me, \n character is enough and the semicolon character is redundant.

He then points to the izs blog posting about it:

http://blog.izs.me/post/2353458699/an-open-letter-to-javascr...

Jacob calls it more 'minimalist' however it does require you to know (and think about) the rules of when Javascript accepts a newline as a line terminator and when it doesn't. In terms of cognitive minimalism 'semis-everywhere' wins. @izs even acknowledges that part of the advantage is forcing the developer to learn:

To the extent that there is an objectively “better” choice, it appears to me that the minimal-semicolon/comma-first style is slightly superior, both because it is fundamentally more scannable and because it encourages programmers to better understand the language they use.

and later:

If you don’t understand how statements in JavaScript are terminated, then you just don’t know JavaScript very well, and shouldn’t write JavaScript programs professionally without supervision, and you definitely should not tell anyone else how to write their JavaScript programs.

He excludes the possibility that you might understand the rules and still prefer to put them everywhere. So all people who disagree with his choice (which he admitted was only slightly better) tend to get categorized as people who don't understand JavaScript very well and we get a new holy war. The fact that all of the JS noobs are lumped on one side of the argument means it's not cool and we can dismiss a well reasoned opinion as ignorance.

All this being said, I personally don't care strongly one way or the other.

eloisius3• 14 years ago

Maybe this kind of reasoning explains why their API is such garbage.

jesseemerick• 14 years ago

I agree. As some-one who has just finished with a large-ish project using bootstrap, I can say that one of the worst parts of it is its js api.

thetrendycyborg5• 14 years ago

This is utterly stupid. And the example he cites for why he prefers an odd function syntax doesn't cause errors..... if you use semicolons.

JavaScript interpreters insert semicolons. If you abuse this, you'll end up with unpredictable results like his function example.

insin3• 14 years ago

The results aren't unpredictable - they're specified exactly, which makes it safe to omit semicolons except where necessary.

You might not know that the return statement is a restricted production, but you do know when you shouldn't immediately follow it with a linebreak.

Similarly, if you see a line beginning with ( or [ which isn't a continuation of the statement on the previous line, stick a semicolon in front of it, or in the case of a wrapped function() {}, use one of the other means of telling the parser it's a function expression. There are other restricted productions, but you just solved every non return-followed-by-linebreak ASI issue I've ever seen in the wild.

ricardobeat15• 14 years ago

Thanks for the kind words. I've been writing javascript like this for more than a year without any trouble. It's not confusing at all, you just need to sit for 5 minutes and understand ASI.

I'd bet with confidence that 90% of programmers out there don't know if a semicolon is needed after a function declaration. They just put it in there blindly, then some day they find a bug because they "forgot" a semi-colon somewhere.

evan_3• 14 years ago

Replying to myself because I decided I have more to say:

Imagine if a coder wrote a big huffy blog post declaring that he was only going to use single-character variables everywhere because it was more "minimalist" than using descriptive variables. He'd be hanged.

Obviously what "fat" is deciding to do with semicolons is less annoying than the strawman I just made up, but I don't think it's entirely dissimilar. The Javascript spec doesn't say that you must use descriptive variables, and using single character variables is certainly valid. However, it's an established convention that we just don't do that, because people find it irritating.

Basically this just comes down to "plays well with others".

rhizome4• 14 years ago

I have to wonder if this is just some invented crisis so this guy can place himself into the tradition of the byte-counting olden days.

evilvoidhamster• 14 years ago

problem here is ruby.ruby developers hate semicolons. They ignore the decades old history opf the semicolon, and assert that the ruby/python/haskell way of indentation and semicolon-less code is the better way. They COULD be right, but im too deep seated in C/C++/Java/JS. One of the problems with javascript is the fact that it gives the choice.

tikhonj2• 14 years ago

Actually, Haskell lets you do it either way. It's the best of both worlds :)

This code:

    do a <- [1,2,3]
       b <- [4,5,6]
       return $ a + b

can also be written as:

     do {
       a <- [1,2,3];
       b <- [4,5,6];
       return $ a + b
     }

or:

     do { a <- [1,2,3]; b <- [4,5,6]; return $ a + b; }

I've even seen it like this:

     do { a <- [1,2,3]
        ; b <- [4,5,6]
        ; return $ a + b }

mrspeaker2• 14 years ago

JavaScript also permits you do it either way. That's what this whole argument is about!

LoneWolf• 14 years ago

Agreed.

The first language I learned was VB6 (ewww), after that C, C++, Java, JavaScript and PHP, only a few years ago I started to hear a lot about Python, Ruby, etc.

I don't see what's the problem with the braces and semicolons, I got used to write them and I don't see it affect my coding speed or code readability, in fact I find it easier to read code with braces and semicolons, I learned a little of python a few months ago and ignoring the fact that I do not know the language syntax very well (or more common libraries) yet, I write it as quickly as I would write Java/C etc, for readability I read python slower but as I said I'm not used to the syntax/libraries/etc yet so that may be the problem.

sunchild• 14 years ago

Actually, it has nothing to do with ruby. The problem here is that some people use minification tools that rely on semicolons. If that weren't the case, this would be a total non-issue.

etfb• 14 years ago

Idealism is like sex: everyone can enjoy it in private, but you shouldn't do it in public unless it's your whole reason for existing.

From this we deduce that Richard Stallman is really Ron Jeremy.

raphinou• 14 years ago

How can ideologies on such futile things as a semi-colon get in the way of playing nice with others? Just put that in perspective with RMS' intransigence in his conviction and fight for freedom. Freedom and semi-colon, which is the more fundamental and worth fighting for?

Rajiv_N4• 14 years ago

I have created a repo at git://github.com/rajivnavada/bootstrap.git that addresses this issue in the Makefile.

Basically, I added a 'proper' target that 'bootstrap' depends on. This target simply adds the semicolon to the end of the file. Hope it helps those of you having problems.

ericflo2• 14 years ago

This is extremely frustrating. I have to create a special code path for Bootstrap JavaScript because it can't be minimized using the standard tooling that works on everything else.

VMG2• 14 years ago

one could argue that the toolchain sucks if it can't process valid JS

ericflo2• 14 years ago

That would also be extremely frustrating if one argued that.

tszming• 14 years ago

Check out the following issue, not just the matter of style..

https://github.com/twitter/bootstrap/issues/401

matt_yoho• 14 years ago

The reply seems immature from the perspective of project maintenance.

brown9-22• 14 years ago

Agreed. Aesthetics should be the first thing to go when they cause real-life issues for what you are making. The only value of the aesthetics of not having semi-colons is to the developer himself.

glenngillen• 14 years ago

That seemed to be a trend in this project, that we briefly overcame: https://github.com/twitter/bootstrap/pull/266

jed_s2• 14 years ago

> many providers (o2, t-mobile, vodafone) across the world embed another js script

> The lack of semi-colons in the dropdown js file causes this compression to break

Thanks for the heads up, no bootstrap for me! (At least without something that's going to add the necessary semicolons... I wonder how many HN weekend projects out there simply don't work for people using their wireless connections?)

Also interesting that it appears the issue was closed because it contained the key phrases 'compression' and 'semicolon'... but it was not re-opened even after the maintainer realized the problem is with the wireless providers.

ricardobeat15• 14 years ago

Even when using semi-colons freely, most people don't put a guarding ; at the beggining or end of the file. That's unrelated to this coding style.

And honestly, that should be done by the minifier. It breaks perfectly valid javascript.

kuahyeow• 14 years ago

This whole thread is probably going nowhere, imo. The maintainer has valid reasons - and it's part of the spec. The issue raisers have their reasons - minifiers don't work for them. Here's the beauty of git and github, one can always run a fork :)

theone• 14 years ago

I don't see it as really a problem. Its just a matter of personal coding preference.

As far as minification and optimization is concerned it works fine using yui, google closure, uglify.js .

(also mentioned by fat in https://github.com/twitter/bootstrap/issues/401#issuecomment...)

josephcooney• 14 years ago

I don't think this is a matter of taste. I think this is showing off for the sake of it.

nornagon• 14 years ago

I avoid using the semicolon in JS because doing so forces me to be aware of the semicolon insertion rules. Forgetting them can lead you to believe that statements like

    return
    { foo: 3 };

do what you expect :)

mcantor• 14 years ago

Why would you ever write that

JackdawX2• 14 years ago

I think this is one of those stylistic preference issues that basically doesn't matter, which is why people will probably go on about it for weeks with no resolution in sight.

Personal anecdote time: I've been writing Javascript for my job for about 16 months now. When I started, I read all the same material as the readers of this site probably did, mostly written by Crockford, advocating a certain brace/semicolon heavy style. But after dutifully following this for about 6 months, I started to notice that I had made many 'mistakes' in the code, to do with missing semis particularly, and so had a lot of other people in the company. Of course, all the code ran fine everywhere and nobody had noticed in 6 months.

So, when writing code for personal exploration at home, I stopped using semis. It's surprising how much time you spend making sure they are there when the interpreter won't check for their presence (and doesn't care either way). Issues can crop up to do with missing semis, but so far I haven't had a single issue, probably because i'm aware of avoiding certain things, like starting a line with a bracket.

So, in my personal experience, it hasn't mattered to have them or not. If you absolutely need them for minification or similar, you should be using a compiler like yui. You are going to make a mistake if your code base is large enough to matter, irrespective of how vigilant you are, so you might as well leave minutiae like this to a computer.

insin3• 14 years ago

Along with not inserting a linebreak immediately after a return (which you must learn whether you use semicolons or not), watching out for lines starting with braces accounts for the vast majority of potential ASI errors you're likely to encounter in the wild (in fact, I don't think I've ever been bitten by ++, unary +/-, or a leading RegExp literal), so it's no wonder you didn't see any issues keeping that one, simple rule in mind.

brown9-22• 14 years ago

Well, this is a stylistic preference issue that does matter if it causes issues for people using certain tools or in certain situations (such as the tethering ISP issue).

eropple2• 14 years ago

I think this is one of those stylistic preference issues that basically doesn't matter, which is why people will probably go on about it for weeks with no resolution in sight.

In theory, yes, it doesn't matter. In practice, it does (and YUI, etc. do not fix the problem):

https://github.com/twitter/bootstrap/issues/401

JackdawX2• 14 years ago

I don't see how this is the original authors problem actually, regardless of the cause. Someones incorrectly written code injected into your own runtime environment could cause all sorts of weird problems.

IMO this is a reasonably serious browser security issue along the same lines as CORS, but thats another argument.

Kiro• 14 years ago

Stupid question maybe but what's wrong with the included bootstrap.min.js? What am I missing?

jed_s2• 14 years ago

Basically, people don't want the minified versions of files while they're developing, and there will always be people coming to the project with whatever minification tools in their build that can't handle the missing semicolons. Currently, the answer is "change your build tools".

https://github.com/twitter/bootstrap/issues/1795

masklinn2• 14 years ago

When things break (and they do) having a stack trace start in the bowels of a minified library is hell. So you'd generally use the "normal" library and the project's minification/concatenation tools.

Even when they handle ASI itself correctly, these tools don't always handle things that nicely across files.

sylvanaar• 14 years ago

This sounds a lot like the spaces vs tabs holy war. The C way vs the Ruby/Python way.

sjwright3• 14 years ago

I wouldn't see any significant problem with a policy of omitting semi-colons when there's no risk of ambiguity, but turning the omission of semi-colons into a religion? That's enough to make me question what other nutty peculiarities exist in his coding philosophy, and therefore whether I'd dare risk my own projects using his library.

ricardobeat15• 14 years ago

It's just embracing the ASI. Nothing wrong with it. On the contrary, the understanding necessary to use it implies good knowledge of the language.

rhizome4• 14 years ago

And is therefore more expensive to maintain.

nostrademons4• 14 years ago

The point of programming is not to show off how well you know the language, else we'd be writing our C in trigrams and our JS in []()+!:

http://discogscounter.getfreehosting.co.uk/js-noalnum.php

sjwright3• 14 years ago

> It's just embracing the ASI.

As opposed to embracing the rationally derived and broadly accepted coding guidelines used by over 99% of open-sourced javascript projects.

I could embrace linguistic documentation and still speak a form of English that would be unnecessarily dense or terse, or just plain incomprehensible to 99% of the English speaking public.

angelortega• 14 years ago

I also hate it. And the colon, for that matter.

beggi• 14 years ago

This has bothered me so many times when using Bootstrap. The compressor I mainly use (UglifyJS) handles the compressing alright, but the concat process fails. At least just have a semicolon at the end of all JS files and that's enough for most people.

ricardobeat15• 14 years ago

http://blog.izs.me/post/2353458699/an-open-letter-to-javascr...

A proper minifier/concatenator will add the necessary shielding semi-colons. Don't use anything that messes with your code without parsing it.

rudiger• 14 years ago

Thanks for drawing my attention to this.

Am I the only one who now won't consider using Bootstrap for a project (based on this semicolon issue)?

phillmv• 14 years ago

Yes.

Or at least, I would still use bootstrap even if I had to throw out all of the js.

Nitramp• 14 years ago

Not having to use semicolons sounds nice, but in practice it can have terrible effects. E.g.:

  var x = function() {
    // something
  }
  
  // avoid polluting global scope:
  (function() {
    // Some initialization.
  })()

This will call the function x with the anonymous function as its argument, and then call the result of that.

There are more examples to that point, and many of them really aren't all that straightforward. So don't rely on automatic semicolons.

Calvein• 14 years ago

You can write this without any problem:

  var x = function() {
    // something
  }

  // avoid polluting global scope:
  !function() {
    // Some initialization.
  }()

evan_3• 14 years ago

So now you've gone from a semicolon, which has the sole purpose of separating statements; to a bang, which doesn't make any sense in this context unless you know that it's replacing a semicolon.

Better or worse?

ricardobeat15• 14 years ago

First commandment of semi-colon-free: any line that starts with [,(,+,- should be prefixed with a semi-colon.

  var x = function() {
    // something
  }
  
  // avoid polluting global scope:
  ;(function() {
    // Some initialization.
  })()

  ;[1,2,3].forEach(...)

In practice those are the only places you'll see (and need) them. It has the extra benefit of disencouraging starting a line with a pre-increment, hacks or weird constructs (not talking of IIFEs of course), and making sure you're never calling a function or accessing properties by accident.

Michiel• 14 years ago

Good advice, and interesting because languages and syntax are interesting to me. But I would never introduce this in my team as a replacement for semicolons at the end of each statement. It seems too random a rule to just follow, hence you'd need to understand the specific problem that it solves. At that point your mental model has become slightly more complex, which doesn't seem worth it.

_gd3l• 14 years ago

Is this really about semicolons, or is it just that with so many fucking people watching, using, and messing around with the bootstrap repo that you're bound to find a bunch of bizarre little edge-case problems? You know what I mean?

My repos don't have a lot of semicolon-related problems, because they don't have almost 20,000 watchers and tons of people using my code.

tlogan• 14 years ago

I want top point out that this shows how it is very very tricky to build a good team. Just imagine that one of your co-workers (very smart, the best, but refuses to understand 'principle of least surprise') is refusing to add semicolons and claiming we now need to change mimifier and change a way how we use 3rd party js dynamic loaders. And that can cause quite unpleased dynamic in the team.

This is one of reasons why companies have strict coding-style guides but that is overhead for a very small company (you don't need coding-style you just need developers which know that code needs to be written with understanding it will also used and maintained by other people in your team).

n8agrin2• 14 years ago

And if your good programming team can't figure out that they might need to edit a coworker's Javascript library to add in missing semicolons in order to cleanly minify their scripts, you have a different (bigger) problem.

ricardobeat15• 14 years ago

It's amazing (and funny) how this whole semi-colon thing is based on fear.

People should understand the role of semi-colons and ASI, just like they should understand the comma operator. It's not hard, takes 10 minutes (read Isaac's post).

Everyone saying that they don't need to understand it is doing a disservice to the community, there's no harm in wanting knowledge of the language to evolve. A few years back people seldomly used IIFEs, and I remember hearing the same argument (wtf is that, don't use it, I don't understand). Change is good.

gmac• 14 years ago

There's no should about it. I know ASI exists, and I also know I need never concern myself with it, because I prefer the simplicity and consistency of finishing each line with a semi-colon.

aidenn0• 14 years ago

Really formatting wars are really stupid. ASI is like indentation, it is trivial to write a program that converts between the two representations. The last time we had an issue about this at work, someone just wrote a pre-commit hook that sets the indentation to be standard without changing the parse tree (it actually asserts the parse tree is the same).

Now you can code any way you want, but no more white-space changes cluttering up the history of files. This is the worst type of holy war because it not only doesn't matter much (which is true of any) but there is a technological solution that the engineers involved are all ignoring.

n8agrin2• 14 years ago

One cold dark night in Javascript-land...

A: Hey, remember when coding was fun? When it was an extension of yourself and you got to create things with it? Create things!

B: No. We're not allowed to do anything except what the Good Book deems acceptable.

A: But, but, you get to take this blank slate and carve out of it whatever you can imagine! Pure expression! And remember when you prioritized your coding style for enjoyment?

B: No. Coding is not fun. Coding is about maximum compliance.

A: ... I remember, but sometimes I think the web has forgotten.

A: I mean think about it. We're banished from the 'new' keyword. We can hardly use polyfills or even extend the native prototypes. How I used to love statements like [[1,2],2,3].flatten(), but lo they are forbidden! Having even one prototype extension in your library is a death sentence. No having fun in Javascript-land!

B: True, fun is not allowed.

A: Hey, what's that over there? That gleaming light coming from the back of that house? Is that a party? Hey it's that house that @fat and @mdo built. They're having fun? We should join them!

B: You don't want to go there man. They don't use semicolons.

A: Is that all they're doing? So what, they're not following the Good Book? They're not afraid to do things a bit out of the ordinary? I'm out of here. See you later Javascript-land. B, I'm going to have some fun with those guys.

B: ... prototype extensions?

(Thanks @fat, @mdo & Twitter for Bootstrap, and for giving it away nonetheless. If I ever have a problem minifying your code, I'll fork it and just add the semicolons myself.)

michaelw• 14 years ago

Has anyone on this thread RTFS?

Semicolons are not optional. They are inserted for you as a convenience when the parser can figure out what you meant.

This situation wasn't a big deal in the early days. But the patterns of coding that have emerged to deal with Javascript's scoping problems have brought this from a curiosity to something profoundly crazy.

Using an operator (i.e. !) to fool the parser is hilarious but really not OK.

Writing code is an exercise in communication. You are communicating with other programmers (including your future self) and the parser. The zero semicolon style espoused by @fat is problematic for both other programmers and the parser. Perhaps one day @fat will win and his style of communication will be sufficiently accepted to be valid but this is not that day.

The relevant section of the ECMAScript spec is included for your convenience:

7.9 Automatic Semicolon Insertion Certain ECMAScript statements (empty statement, variable statement, expression statement, do-while statement, continue statement, break statement, return statement, and throw statement) must be terminated with semicolons. Such semicolons may always appear explicitly in the source text. For convenience, however, such semicolons may be omitted from the source text in certain situations. These situations are described by saying that semicolons are automatically inserted into the source code token stream in those situations.

http://www.ecma-international.org/publications/standards/Ecm...

Bootstrap's maintainer hates the semicolon

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