Darren New escreveu:
> Sure. Using C as an intermediate language for another language that's 
> basically C-ish is probably a good idea.

Scheme is very unlike C, both obviously in syntax but also in semantics: 
  no low-level type declares, higher-order functions receiving or 
returning functions, unlimited lexical scoping, unrestricted 
higher-order continuations.  Syntatic abstraction doesn't even come into 
play for semantics as it's processed before being compiled to C.

Still, C is a very preferred target for Scheme fast code generators. 
Many translation techniques have matured and proven very useful in using 
C as intermediate language.

> I was merely arguing that the 
> idea that "my language runs as fast as C code" is not obviously true 
> from the fact that it uses C as an intermediate language.  Using C as an 
> intermediate language doesn't make it trivial to run as fast as 
> hand-rolled C.

Not obvious, yes.  It works by using C as assembly rather than as a 
third generation high-level language as it once was.  They use many 
dirty tricks that no one using C to directly write programs in would 
think of, like agressive loop unrolling and optimization and constant 
folding before generating any C code.  Much of the C "code" is actually 
C preprocessor macros.

Yes, it will never be as fast as C obfuscated and cryptic code written 
by hand by a hacker, but the point is not that:  it is to write very 
high level code that still performs quite favorably to low-level C as 
assembly.

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