Nicolas Calimet <pov### [at] freefr> wrote:
>         But in what language the C++ streams are implemented internally ?
> Isn't it mostly in C and asm ?  The C libraries usually are too.

>         I'm interested in this particular point since my own projects
> rely _a lot_ on labelled data (using my own C string "library").  Could you
> give an example where C++ strings clearly outperform the equivalent C code
> (if anything similar can be done) ?

  I think you are confusing "string" and "stream" above. They are two
quite different things... :)

  I was talking about std::string.
  Almost *any* operation on a std::string is faster than an equivalent
operation on a C string. The simplest example is getting the size
of the string.
  std::string::size() is a constant-time operation (it simply returns
the value of a variable), while strlen() goes through the entire string
to get its size. Now, imagine that the string is 100 million characters
long...

>         Ah ! Since I usually write GB of data, it seems that I still have
> a good reason to "kiss" C a bit longer  ;-)

  If you do it right, you can change from one to the other by changing
just a few lines of code (no matter how many millions of lines long is
your whole program). That's what modularity is about.
  (If you do it wrong and you want to change it, you'll have to go
through the millions of lines and change every place where it's
used... Remember y2k?-) )

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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