Re: *.mid vs *.midi

[Hans Aberg]

On 18 May 2008, at 19:55, immanuel litzroth wrote:

> > > > So the C language itself does not
> > > > have any #include directive.
>
> The C language standard is available at:
> http://www.open-std.org/JTC1/SC22/WG14/www/docs/n1256.pdf
> You'll see all the preprocessing directives explained there and no  
> mention of a separate preprocessor program.

Sure: it just defines the two languages, without explicitly  
mentioning their grammar sentence symbols. So it is formally  
impossible to deduce it from the standards alone. Somebody pointed  
this out to me. The C++ standardization committee felt this was clear  
enough, since the standard does not include a formal grammar, but jut  
an informal description of it.

> The introduction does say: "A C program need not all be translated  
> at the same time".

This refers to the C/C++ grammar sentence symbol called "translation- 
unit". Translation units can be compiled separately at different  
times and later linked together using the C linker.

> > This is probably just to define the language semantics.
> That's my point, semantically the inclusion models are the same.

It just describes the module effect of name separation.

> Haskell does not define how modules are mapped to files, how they  
> are searched for...

The point is to not do that, but keep the information within the  
language, so that a better analysis of dependencies can be done.

> ...and how to "figure out" what to include in a compilation. These  
> are implementation issues.

In Haskell, you really only need to tell what you need, not worrying  
how it should be included syntactically (though the location of the  
module must somehow be given)). In each module one tells what other  
modules it may depend on, and then Haskell figures out out to link  
them together. This is different from C/C++ where one by hand has to  
make the file inclusions i the right order and put in guards to that  
files are not include more than once, so that hopefully a series of  
translation units are created which can be linked together by the C  
linker.

  Hans