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Brendan Eich: The infernal semicolon

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Re: Brendan Eich: The infernal semicolon

#81

Post by web_chops »

cletus wrote: post #33

Heh, I was waiting for this post. Coming in the next 24 hours: - "Why I use minimal semi-colons in Javascript" - "ASI is broken but I like it" Honestly I'm shocked at the defense of this practice (of ASI "abusage"). It speaks loudly to Jacob's (fat@githib) ranking of ego-stroking and showboating over creating readable code, particularly for a library "Designed for everyone, everywhere" [1]. I'm confounded that such a…

That is what surprised me a lot. That there would be so much defense of the practice. I work on C/C++ for a living in enterprise environment and there are style rules followed diligently. Every one knows that there can be lot of cool/hipster code written with C/C++ but no one does because of the maintenance concerns. Writing code is much easier than maintaining it.

Re: Brendan Eich: The infernal semicolon

#82

Post by web_chops »

BrendanEich wrote: post #46
_delirium wrote: post #36

Earlier quoted context omitted.

Given that these are all formal languages, though, isn't that equivalent to saying that ASI is, formally speaking, part of the language's syntax? It's all just parsers! Apart from the social conventions around them, of course.

No, there's an important distinction. ASI does not even kick in without a syntax error. Yet the "expectation of ASI" or (I think more likely) "expectation of newline significance" makes people believe that they'll get a ; inserted by separating two things by one or more newlines. Most languages do not specify error correction. HTML5 of course does; CSS too; among general programming languages it's much less common. T…

I'm curious, does ASI actually hurt the performance of JS parsing ? I mean, will there be any performance difference between a code that properly uses semicolons versus one that relies on ASI..

Re: Brendan Eich: The infernal semicolon

#83

Post by enneff »

raganwald wrote: post #9
enneff wrote: post #7

Earlier quoted context omitted.

That doesn't sound right to me. Making s language's syntax more liberal is not a sane way to correct errors. If anything, JavaScript's ASI is an error creation mechanism.

"Here is your new apartment. You must use a key to enter it. If you forget your key, you can buzz the superintendent during business hours, and if the super is home, (s)he will open the door for you.” If you try to take your key with you at all times, the super will save your bacon once in a blue moon when you forget your key. On the other hand, if you think of the door as only needing a key when you wish to have it…

This is not a good analogy. More like the superintendant will let you into a different apartment, or let you into your apartment and then punch you in the face. You just don't know.

But you don't need analogies to understand why ASI is a bad idea. ASI means that when you leave out a semi-colon you get unexpected behavior instead of a syntax error. Failure is always better than the unknown. At least then there's a chance the bug will be found and fixed.

Re: Brendan Eich: The infernal semicolon

#84

Post by gcb »

dave1010uk wrote: post #68
gcb wrote: post #13

if ; (x3B?) and \n (x0A) are the same size, why use ; in minified JS if \n has more "features"

Some reasons: \n can easily get turned into \r\n Whitespace is harder to see when debugging (especially with word wrap) Convention

You're not supposed to touch your minified js after you generated it

Re: Brendan Eich: The infernal semicolon

#85

Post by pbiggar »

Tichy wrote: post #54
edwinnathaniel wrote: post #15

If a major framework breaks a major toolchain and they both disagree on a fundamental principal, then they both don't promote pragmatism or "Get Things Done".

My takeaway is that it really is time to try coffeescript :-/

You will not regret it.

Re: Brendan Eich: The infernal semicolon

#86

Post by nhebb »

cletus wrote: post #33

Heh, I was waiting for this post. Coming in the next 24 hours: - "Why I use minimal semi-colons in Javascript" - "ASI is broken but I like it" Honestly I'm shocked at the defense of this practice (of ASI "abusage"). It speaks loudly to Jacob's (fat@githib) ranking of ego-stroking and showboating over creating readable code, particularly for a library "Designed for everyone, everywhere" [1]. I'm confounded that such a…

The GitHub style guide recommends the opposite:

"Do your best to never use a semicolon. This means avoiding them at line breaks and avoiding multi-statement lines. For more info, read Mislav's blog post [2]."

FWIW, I agree with the Google style guide. Maybe I'm interpreting it wrong, but ASI struck me as a fail-safe to protect coders that forgot the occasional semicolon and was later mis-identified as a feature. Having Brendan Eich weigh in on this is akin to having Thomas Jefferson pop his head into the Ninth Circuit and clarify an issue over Constitutional intent. If it were me, I'd listen to Thomas Jefferson.

[1] https://github.com/styleguide/javascript

[2] http://mislav.uniqpath.com/2010/05/semicolons/

Re: Brendan Eich: The infernal semicolon

#88

Post by Lewisham »

cletus wrote: post #33

Heh, I was waiting for this post. Coming in the next 24 hours: - "Why I use minimal semi-colons in Javascript" - "ASI is broken but I like it" Honestly I'm shocked at the defense of this practice (of ASI "abusage"). It speaks loudly to Jacob's (fat@githib) ranking of ego-stroking and showboating over creating readable code, particularly for a library "Designed for everyone, everywhere" [1]. I'm confounded that such a…

What surprises me is not that Fat is a bit of a jerk (note, I "get" it, but I don't respect it), but that Twitter lets him keep being a jerk and actively hostile while acting as a representative of the company.

If he wrote Bootstrap by himself, he's free to call every single user an idiot if he wishes, but when it's being released as a Twitter product, one would think Twitter would demand some modicum of respect to be shown. Can you imagine a Googler acting this way on the Chromium or Android projects? Yeah, there are decisions made on those where people aren't happy, but the comments aren't laden with zingers either.

If Douglas Crockford comes down and tells me I'm doing JavaScript wrong, I would hope I'd show a bit more respect to someone who's most likely my better.

Re: Brendan Eich: The infernal semicolon

#89

Post by aubergene »

Natsu wrote: post #60
cletus wrote: post #33

Heh, I was waiting for this post. Coming in the next 24 hours: - "Why I use minimal semi-colons in Javascript" - "ASI is broken but I like it" Honestly I'm shocked at the defense of this practice (of ASI "abusage"). It speaks loudly to Jacob's (fat@githib) ranking of ego-stroking and showboating over creating readable code, particularly for a library "Designed for everyone, everywhere" [1]. I'm confounded that such a…

I'm surprised no one has made a little command line tool that follows the rules and automatically inserts semicolons according to the ASI spec. That might even be useful.

Closure linter's fixjsstyle can do this

https://developers.google.com/closure/utilities/

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