Re: MoonScript, a language that compiles to Lua

[leaf corcoran <leafot@...>]

Thanks for the huge list of suggestions. I'm still adding to the
syntax so this kind of input is helpful.

> * You could adopt the YAML syntax for arrays:
I definitely want to do this. I think CoffeeScript already supports
this syntax, so I'd like to follow there.

> * For function calls, allow new lines+indentation as a substitute for
> comas, and an initial new line.
This is a an interesting idea. It would work great for creating a DSL
with your own constructs.

> > * In tables, make the square brackets optional for string literals (I
> > think it is unambiguous).
> I meant in table keys.
I don't see any problems with this.


> * you can use "if expression then end" rather than assignment to _ to
> turn expressions into valid statements. I think it is cheaper (but I
> didn't test it, and I may be wrong)

Interesting, I haven't thought of this. I'll have to test it.

Thanks


2011/8/13 Pierre-Yves Gérardy <pygy79@gmail.com>:
> This is beautiful :-)
>
> I've been working  for some time on and off on an almost identical
> project (called Venus), but I never got around to have something
> presentable.
>
> Based on that, I have a few suggestions:
>
> * You could adopt the YAML syntax for arrays:
>   - prefixing, each
>   - line, with
>   - dashes.
> It would provide a complete common subset between the MoonScript table
> syntax and YAML.
>
> * For function calls, allow new lines+indentation as a substitute for
> comas, and an initial new line.
>
> You_could
>   call_a_function
>   with_several
>   long_arguments.
>
> If you need to pass several table literals, they can be
> wrapped
>   ( between: parentheses
>     like: this )
>   ( and: this )
>
> (Now
>   (some S-expressions)
>   (are also
>       valid))
> :D
>
>
> * In tables, make the square brackets optional for string literals (I
> think it is unambiguous).
>
> * the two underscores before the init metamethod uglify the
> declaration for (IMO) no good reason beside following the Lua
> metamethod naming convention. If you want to keep them in the
> metatable key, I'd suggest creating a special case in the class
> parsing routine to detect an "init" key and prepend the underscores
> automatically.
>
> * How do you declare upvales without assigning to them? As follows? I
> wish there was a nicer option (but it is not very important).
>
> a, b = nil
> z = () ->
>  a=3
>
> * a custom syntax to automatically hoist functions out of loops, to
> prevent lambda creation at each iteration of the loop.
>
> sort collection do |a,b| a > b --Ruby inspired?
>
>
> Expressions as statements are great for DSLs. The table literals also
> allow to prepend comments, in a way:
>
> foo = ()->
>  initialize: init!
>  some_more_stuff: bang(bar)
>
> Evil >:-D
>
> * you can use "if expression then end" rather than assignment to _ to
> turn expressions into valid statements. I think it is cheaper (but I
> didn't test it, and I may be wrong)
>
> * A combo: 1) prepend the last expression of a file with return. 2)
> turn contiguous table definitions at the current level of indentation
> into one table rather than several. Then you can have a file like
> this:
>
> a:b
> b:c
>
> compliled into "return {a=b,b=c}".
>
> As far as I understand, it is compatible with the semantics of your
> language, and it gives you the most beautiful configuration files in
> the world.
>
> Kind regards
> -- Pierre-Yves
>
>
> On Thu, Aug 11, 2011 at 08:10, leaf corcoran <leafot@gmail.com> wrote:
>>
>> Hello,
>>
>> I've been working on a little language heavily inspired by
>> CoffeeScript, which I've called MoonScript. The homepage is located at
>> http://moonscript.org
>>
>> It compiles into Lua, but there are numerous ways to actually run the code.
>>
>> The parser is all done in LPeg, and the majority of the compiler
>> itself is written in MoonScript. I've also used a few other libraries
>> (listed on the site) to build the tools.
>>
>> I've also written copious amounts of documentation in the hopes that
>> someone will actually use it, http://moonscript.org/reference
>>
>> The source is located on GitHub: https://github.com/leafo/moonscript
>>
>> I've successfully installed it with LuaRocks on both Linux and OSX. I
>> have not tried it on Windows, but I don't see why it wouldn't work.
>>
>> I think there's some pretty cool stuff in it. By just requiring
>> "moonscript", you can make the require function MoonScript aware and
>> have it automatically build and run .moon files as you would with .lua
>> files. I've also got line number reversal, so errors that happen in
>> the compiled Lua are rewritten to point back to the original
>> MoonScript line.
>>
>> Anyway, check it out the docs to see the rest of the features. I'd
>> appreciate any input (including feature requests). This is the initial
>> release so there might be some bumps.
>>
>> Thanks, Leaf
>>
>
>