Re: Upstream is not the last word (was Re: [ANN] Lua 5.1.5 (rc1) now available)

[Ross Bencina <rossb-lists@...>]

On 14/02/2012 9:15 PM, Josh Simmons wrote:
> Not quite sure what you were saying before about standard container
> classes? This is Lua after all, and we have the wondrous table which
> manages quite well to subsume the common data structures.

I know the argument is getting old, just to clarify what I mean by 
standard containers (maybe I mean "collections" if there's a 
difference): I agree that table handles the mechanism, but it says 
nothing about the intended use, nor does it's interface limit its use to 
valid semantics of a specific container type. When I need a LIFO stack, 
I want to write something that encodes the intent:

s = Stack();
s:push( 1 );
s:push( 2 );

print( s:pop() );
-- 2
print( s:pop() );
-- 1

Other useful container/collection abstractions with reasonably universal 
semantics in different languages: Queue, Set, Deque, Bag

I won't bore you with a defense of "say what you mean, and make it hard 
to do what you don't mean." I program in assembly language sometimes 
too, but when I'm using a scripting language I want abstraction and 
clarity, not to have to consult my decoder ring "what's the most 
efficient way to make a table behave like an X".

I'm not so accross the functional side of things so much but map() and 
filter() might be common examples there.


> Anyway as has previously been mentioned if you're serious about this
> kinda stuff the best bet would probably be to contribute to penlight
> (or that other one). Those of us who don't prefer to add dependencies
> are not likely to change our minds and join the cause any time soon
> however if penlight continues to become more compelling it may become
> something of a de facto standard, which is about the best you could
> hope for as far as I can see.

Thanks for the advice. Sounds like I better invest some time learning 
about these.

Maybe there could be a new entry in the uFAQ, something like:

>>>>>>>>>>>>>>>>>

Q: Where's the library of basic primitives (object system, collections, 
functional programming primitives, etc)?

A: Lua comes "without batteries". You're expected to roll your own or 
concoct something from the many and diverse sources out there. If you're 
looking for something approaching a base library that you can include in 
your project out of the box you might be interested in checking out 
penlight [http://stevedonovan.github.com/Penlight/] or stdlib 
[http://luaforge.net/projects/stdlib, 
http://lua-users.org/wiki/StandardLibraries]. These are not yet de fecto 
standards but if you start using them they may become so one day.

<<<<<<<<<<<<<<<<<


Cheers,

Ross.