Re: simple vs complex languages

Steve_Lipscombe@amat.com wrote in message news:03-04-095...
> Robert wrote
>
> If a language is designed with a simple, consistent syntax then it is
> not only easier for the compiler to parse, but (more importantly) it
> is easier for humans to understand and therefore easier to get
> right. Can you guess I like Pascal, which was designed from the outset
> for a single pass RDP?
>
> I'm no expert in these matters (then shut-up, they cried), but it
> seems to me that to express complex ideas we need a rich vocabulary,
> but not a complex syntax. And if not, then why do we do it?


Consider modern declarative languages like Haskell and Mercury. Each
effectively has a core syntax, which is easy to understand on the
small scale and in which one can write programs directly. However,
various items of syntactic sugar (i.e. non-core syntax that is
translated into core syntax) are part of these languages because the
syntactic sugar is so useful.


For example, one does not *need* to use multiple clauses or pattern
matching in the head or syntactic sugar for lists or convenient syntax
for type classes et cetera, but without them programs are harder to
read.


Syntactic sugar is added (conservatively) to simplify common cases. It
is usually not hard to parse and easy to translate into core syntax.


> Why make anything needlessly complicated? Just to prove how clever we are?


Only Lisp programmers think Lisp programs are a model of clarity :-)


> Human languages are too ambiguous for programming. They only work for
> humans because we add redundant information, use context to resolve
> ambiguities, or simply make assumptions (which sometimes/often turn
> out wrong).


Indeed and somebody should tell this to Larry Wall and the little Perl
Wizards.


> Finally, if you want to program in a human language, try parsing this old
> favourite:
>
> Time flies like an arrow, fruit flies like a banana.


Parsing isn't the problem with this old chestnut.


- Ralph

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