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Weird Lexical Syntax

justine.lol

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Re: Weird Lexical Syntax

#201

Post by James_K »

mqus wrote: post #46
__MatrixMan__ wrote: post #33

This was a fun read, but it left me a bit more sympathetic to the lisp perspective, which (if I've understood it) is that syntax, being not an especially important part of a language, is more of a hurdle than a help, and should be as simple and uniform as possible so we can focus on other things. Which is sort of ironic because learning how to do structural editing on lisps has absolutely been more hurdle than help s…

Having a simple syntax might be fine for computers but syntax is mainly designed to be read and written by humans. Having a simple one like lisp then just makes syntactic discussions a semantic problem, just shifting the layers. And I think an complex syntax is far easier to read and write than a simple syntax with complex semantics. You also get a faster feedback loop in case the syntax of your code is wrong vs the…

I've always thought these complaints are really just a reflection of how stuck we are in the C paradigm. The idea that you have to edit programs as text is outdated IMO. It should be that your editor operates on the syntax tree of the source code. Once you do that, the code can be displayed in any way.

Re: Weird Lexical Syntax

#202

Post by styglian »

mistercow wrote: post #56
skitter wrote: post #7

Another syntax oddity (not mentioned here) that breaks most highlighters: In Java, unicode escapes can be anywhere, not just in strings. For example, the following is a valid class: class Foo\u007b} and this assert will not trigger: assert // String literals can have unicode escapes like \u000A! "Hello World".equals("\u00E4");

I also argue that failing to syntax highlight this correctly is a security issue. You can terminate block comments with Unicode escapes, so if you wanted to hide some malicious code in a Java source file, you just need an excuse for there to be a block of Unicode escapes in a comment. A dev who doesn’t know about this quirk is likely to just skip over it, assuming it’s commented out.

I once wrote a puzzle using this, which (fortunately) doesn't work any more, but would do interesting things on older JDK versions: https://pastebin.com/raw/Bh81PwXY

Re: Weird Lexical Syntax

#204

Post by wslh »

kergonath wrote: post #182
wslh wrote: post #176

Earlier quoted context omitted.

My question was precisely about why the user like trigraphs over using just || on this case. It is a very clear question and makes all the sense.

The post shows a “favorite C trigraph” thing, not that they were going out of their way to use trigraphs in actual code or that you should. Using trigraphs is the whole premise so no, your question makes no sense in that context. FWIW the ??!??! double trigraph as error processing is funny because of the meaning of ?! and various combinations of ? and !. It is funny and it has trigraphs. That’s the whole point.

> The post shows a “favorite C trigraph” thing, not that they were going out of their way to use trigraphs in actual code or that you should.

But I am free to be curious and ask the author why he choose it! We are not computers but human beings! There is no HN rule that says that I cannot be curious and asks a question that arised from a thread but it is not connected to that! [1].

[1] https://www.iflscience.com/charles-babbage-once-sent-the-mos...

Re: Weird Lexical Syntax

#205

Post by JadeNB »

samatman wrote: post #130
wslh wrote: post #125

Earlier quoted context omitted.

Could you review my comment on HN? Please educate me if there is something I haven’t understood, rather than downvoting my question.

The grandparent post is specifically about trigraphs. Saying something about trigraphs was the end-in-itself, trigraphs were chosen to illustrate something about trigraphs. So your question made no sense. Hope that helps.

> So your question made no sense. Hope that helps.

I think that is uncharitable. The question ("Did you choose the legacy C trigraphs over || for aesthetic purposes?") makes perfect sense to me. I think context makes it reasonably clear that the answer is 'yes,' but that doesn't mean that the question doesn't make sense, only perhaps that it didn't need to be asked.

Re: Weird Lexical Syntax

#206

Post by wslh »

teo_zero wrote: post #180
wslh wrote: post #176

Earlier quoted context omitted.

My question was precisely about why the user like trigraphs over using just || on this case. It is a very clear question and makes all the sense.

I didn't downvote your comment but understand why it looks "wrong": it's like, in a thread on English oddities, you replied to someone bringing up the "buffalo buffalo buffalo" example with the question "why are you so fond of bovines"?

It has nothing to do with that. I could ask why he didn't choose a different homonymic ambiguity [1].

[1] https://journals.linguisticsociety.org/proceedings/index.php...

Re: Weird Lexical Syntax

#207

Post by kryptiskt »

SuperCuber wrote: post #89
drewr wrote: post #61

Earlier quoted context omitted.

I don't understand your distinction between syntax and semantics. If the semantics are complex, wouldn't that mean the syntax is thus complex?

lisp's syntax is simple - its just parenthesis to define a list, first element of a list is executed as a function. but for example a language like C has many different syntaxes for different operations, like function declaration or variable or array syntax, or if/switch-case etc etc. so to know C syntax you need to learn all these different ways to do different things, but in lisp you just need to know how to match…

Lisp has way more syntax, that doesn't cover any of the special forms. Knowing about application syntax doesn't help with understanding `let` syntax. Even worse, with macros, the amount of syntax is open-ended. That they all come in the form of S-expressions doesn't help a lot in learning them.

Re: Weird Lexical Syntax

#208

Post by jacobn »

TomatoCo wrote: post #45

I think my favorite C trigraph was something like do_action() ??!??! handle_error() It almost looks like special error handling syntax but still remains satisfying once you realize it's an || logical-or statement and it's using short circuiting rules to execute handle error if the action returns a non-zero value.

https://en.wikipedia.org/wiki/Digraphs_and_trigraphs_(progra...

??! Is converted to |

So ??!??! Becomes || i.e. “or”

Re: Weird Lexical Syntax

#209

Post by jart »

vidarh wrote: post #187
pdw wrote: post #22

Some random things that the author seem to have missed: > but TypeScript, Swift, Kotlin, and Scala take string interpolation to the furthest extreme of encouraging actual code being embedded inside strings Many more languages support that: C# $"{x} plus {y} equals {x + y}" Python f"{x} plus {y} equals {x + y}" JavaScript `${x} plus ${y} equals ${x + y}` Ruby "#{x} plus #{y} equals #{x + y}" Shell "$x plus $y equals $…

Ruby takes this to 100. As much as a I love Ruby, this is valid Ruby, and I can't defend this: puts "This is #{ Just to combine the string interpolation with her concern over Ruby heredocs. My other favorite evil quirk in Ruby is that whitespace is a valid quote character in Ruby. The string (without the quotes) "% hello " is a quoted string containing "hello" (without the quotes), as "%" in contexts where there is n…

https://pbs.twimg.com/media/GbEfj6fbQAQRUB7?format=png&name=...

That's so going in the blog post later today.

Re: Weird Lexical Syntax

#210

Post by mdaniel »

James_K wrote: post #201
mqus wrote: post #46

Earlier quoted context omitted.

Having a simple syntax might be fine for computers but syntax is mainly designed to be read and written by humans. Having a simple one like lisp then just makes syntactic discussions a semantic problem, just shifting the layers. And I think an complex syntax is far easier to read and write than a simple syntax with complex semantics. You also get a faster feedback loop in case the syntax of your code is wrong vs the…

I've always thought these complaints are really just a reflection of how stuck we are in the C paradigm. The idea that you have to edit programs as text is outdated IMO. It should be that your editor operates on the syntax tree of the source code. Once you do that, the code can be displayed in any way.

I also believe this, and we're actually about half way there via MPS https://github.com/JetBrains/MPS#readme> but I'm pretty sure that dream is dead until this LLM hype blows over, since LLMs are not going to copy-paste syntax trees until the other dream of a universal representation materializes[1]

1: There have been several attempts at Universal ASTs, including (unsurprisingly) a JVM-centric one from JetBrains https://github.com/JetBrains/intellij-community/blob/idea/24...

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