Sylph: the programming language I want • Hacker News Board

Re: Sylph: the programming language I want

#21

Post by TazeTSchnitzel » Sun, Mar 01, 2015, 2:54 PM UTC

geocar wrote: post #13

seanmcdirmid wrote: post #5

Earlier quoted context omitted.

The computer is really quite proficient at inferring block structure from indentation, and if you use a modern editor this structure is manipulated rather effortlessly. The main problem with indent oriented languages is that not everyone is or wants to use a modern editor. Then there are LISPers who think braces everywhere are a swell idea.

> The computer is really quite proficient at inferring block structure from indentation, and if you use a modern editor this structure is manipulated rather effortlessly. Nonsense. Try pasting a block of Python into Hacker News and you get something that starts off like this: import os import random def do_something(x): if x: fd = os.open(x) and only gets worse. A language with braces/semicolons has no such problem;…

C code with whitespace and new lines stripped is equally unreadable.

You are arguing that braces should be kept so people who don't indent their code properly on HN can be understood.

Re: Sylph: the programming language I want

#22

Post by TazeTSchnitzel » Sun, Mar 01, 2015, 2:55 PM UTC

gnuvince wrote: post #14

okasaki wrote: post #3

>If your language has braces, then you are indenting for the sake of humans (because humans are good at noticing alignment and edges), and bracing for the sake of computers. That’s double the effort for something as mundane as where a block ends. If they get out of sync, then your code naturally breaks in a way that’s very difficult for you to detect. No, I use braces for the computer, and the computer automatically…

I like writing compilers, how do languages like Haskell and Python handle blocks-by-indentation? I figure you have some sort of INDENT token, but how do you know its width? Also, in specifying the grammar, with explicitly delimited blocks you just say `block := OPEN stmt_list CLOSE`. What about with indentation?

I think they specify "INDENT foo DEDENT" and the lexer tracks indentation and issues INDENT/DEDENT as appropriate.

Re: Sylph: the programming language I want

#23

Post by deckiedan » Sun, Mar 01, 2015, 3:01 PM UTC

A lot of syntax / spacing / etc. problems would go away if we stopped using completely plain text as the medium for programming languages. Or rather, if we extended plain text, or got our editors to understand the languages a bit more thoroughly than just highlighting keywords and giving us autocompletion or whatever. This has been explored a bit by michaelw and others (http://www.foldr.org/~michaelw/emacs/) for lisp.

Imagine a syntax aware editor which could display code from a language using the syntax or style of another. (This might only work from a single base language, there are too many "odd" features in languages which couldn't translate universally).

So, since I like python, it could be displayed PEP8 style. Someone else could see it with LISP braces everywhere. Another could have it with 2 spaces and 'end' keywords, or {curlybraced;} (in K&R style, or whatever you like).

Re: Sylph: the programming language I want

#24

Post by geocar » Sun, Mar 01, 2015, 3:03 PM UTC

vertex-four wrote: post #17

geocar wrote: post #13

Earlier quoted context omitted.

> The computer is really quite proficient at inferring block structure from indentation, and if you use a modern editor this structure is manipulated rather effortlessly. Nonsense. Try pasting a block of Python into Hacker News and you get something that starts off like this: import os import random def do_something(x): if x: fd = os.open(x) and only gets worse. A language with braces/semicolons has no such problem;…

> A language with braces/semicolons has no such problem; it is easier to communicate with others If someone posts more than two lines of practically any curly-brace language as one line, it's illegible. Yes, you can pull it into an editor and fix it automatically, but it's a huge waste of time that is best fixed by simply posting the code properly in the first place.

> any curly-brace language as one line, it's illegible.

You might not be able to read it, but others can, so it is by definition not illegible.

"Indention language", on the other hand, has actually lost its meaning and therefore is illegible.

> it's a huge waste of time that is best fixed by simply posting the code properly in the first place

Helping others is never a waste of time, but telling people thy are too stupid to ask for help correctly is cruel.

Re: Sylph: the programming language I want

#25

Post by DanWaterworth » Sun, Mar 01, 2015, 3:04 PM UTC

ahoge wrote: post #19

The inference example is actually a good illustration for why you want to add types to a function's signature. As the author mentioned, a machine can look at how the arguments are used and make some educated guesses. The big problem is that humans have to do the same. That's why I like optional types à la Dart. Not only do they help with static analysis, they also act as documentation. With a good editor, this docume…

> a machine can look at how the arguments are used and make some educated guesses. The big problem is that humans have to do the same.

Why? Just get the machine to do it.

It's like when you see programmers doing arithmetic in their heads. "You're sitting in front of a glorified calculator!"

Re: Sylph: the programming language I want

#26

Post by gus_massa » Sun, Mar 01, 2015, 3:05 PM UTC

geocar wrote: post #13

seanmcdirmid wrote: post #5

Earlier quoted context omitted.

The computer is really quite proficient at inferring block structure from indentation, and if you use a modern editor this structure is manipulated rather effortlessly. The main problem with indent oriented languages is that not everyone is or wants to use a modern editor. Then there are LISPers who think braces everywhere are a swell idea.

> The computer is really quite proficient at inferring block structure from indentation, and if you use a modern editor this structure is manipulated rather effortlessly. Nonsense. Try pasting a block of Python into Hacker News and you get something that starts off like this: import os import random def do_something(x): if x: fd = os.open(x) and only gets worse. A language with braces/semicolons has no such problem;…

[Note: if you add two spaces at the beginning of each line, it will look like code:

  import os 
  import random 
  def do_something(x):
    if x:
      fd = os.open(x)

Note2: If one line with two spaces is too long, it will mess the whole thread, so if you ever want to quote use italics instead of spaces.]

Re: Sylph: the programming language I want

#27

Post by wolfgke » Sun, Mar 01, 2015, 3:06 PM UTC

geocar wrote: post #13

seanmcdirmid wrote: post #5

Earlier quoted context omitted.

The computer is really quite proficient at inferring block structure from indentation, and if you use a modern editor this structure is manipulated rather effortlessly. The main problem with indent oriented languages is that not everyone is or wants to use a modern editor. Then there are LISPers who think braces everywhere are a swell idea.

> The computer is really quite proficient at inferring block structure from indentation, and if you use a modern editor this structure is manipulated rather effortlessly. Nonsense. Try pasting a block of Python into Hacker News and you get something that starts off like this: import os import random def do_something(x): if x: fd = os.open(x) and only gets worse. A language with braces/semicolons has no such problem;…

Just put two spaces before each line (https://news.ycombinator.com/formatdoc: "Text after a blank line that is indented by two or more spaces is reproduced verbatim. (This is intended for code.)"):

  import os
  import random
  
  def do_something(x):
    if x:
      fd = os.open(x)

Re: Sylph: the programming language I want

#28

Post by masklinn » Sun, Mar 01, 2015, 3:07 PM UTC

seanmcdirmid wrote: post #12

marcosdumay wrote: post #11

Earlier quoted context omitted.

What's effortless is putting begin and end of blocks symbols only where they matter. Haskell is particularly guilty of creating several different indenting possibilities, and does require constant intervention. Python is less bad, but still requires more effort than C for example.

You really have to design your language around it for it to work well. Haskell has a a lot of syntactic craziness in the name of simplicity.

What? Haskell has a base language expressed in terms of braces and semicolons, and a relatively simple set of layout rules defining how the compiler can insert these braces and semicolons automatically.

Re: Sylph: the programming language I want

#29

Post by masklinn » Sun, Mar 01, 2015, 3:09 PM UTC

marcosdumay wrote: post #11

seanmcdirmid wrote: post #5

Earlier quoted context omitted.

The computer is really quite proficient at inferring block structure from indentation, and if you use a modern editor this structure is manipulated rather effortlessly. The main problem with indent oriented languages is that not everyone is or wants to use a modern editor. Then there are LISPers who think braces everywhere are a swell idea.

What's effortless is putting begin and end of blocks symbols only where they matter. Haskell is particularly guilty of creating several different indenting possibilities, and does require constant intervention. Python is less bad, but still requires more effort than C for example.

Er… you know Haskell's syntax is defined as braces-and-semicolons right? And the braceless-and-semicolons-free syntax is the addition of a few layout rules[0] for human convenience.

[0] https://www.haskell.org/onlinereport/syntax-iso.html#sect9.3

Re: Sylph: the programming language I want

#30

Post by brudgers » Sun, Mar 01, 2015, 3:13 PM UTC

This reminds me of reading a typical zoning ordinance: more an historical sack of bandaid reactions to specific but unrelated past problems than a positive program generating a bounded creative domain. Addressing gripes is not evaluating tradeoffs.

Successful languages start with a clear idea of what problem they want to solve, creating coherency at a high level. Values are ranked and might be nice is distinguished from what is held dear. The starting point is identifiable and the passion positive. Saying "the ending point is not here," isn't enough.