Orchid XP v8 wrote:
>>> Haskell really is a PITA to parse. I mean, think about it:
>>> - Whitespace is significant. (No context-free parsing here!)
>>
>> I don't think "context-free" means what you think it means. Whitespace 
>> being significant isn't "context".
> 
> Indentation is significant. To parse the next line, you must know how 
> far the current line was indented. Hence, "context".

I don't think "context-free" means what you think it means.

That's like saying Pascal isn't context-free because you need to know how 
many "begin" statements you're nested within.

A grammar is context-free if none of the left side of the production have 
terminal symbols in them.  (That's the technical definition, which takes 
several paragraphs to explain in prose.)

> No, they can be used *before* they're defined. And they can be defined 
> in a completely seperate source file too. Which makes me wonder how it's 
> possible to parse an individual file at all... you'd need to potentially 
> parse every module it imports to work out the operator precedences!

Could be! :-)  Sounds like a real bear to compile, but then, that's what 
computers are for.

-- 
   Darren New, San Diego CA, USA (PST)
   "We'd like you to back-port all the changes in 2.0
    back to version 1.0."
   "We've done that already. We call it 2.0."

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