Re: boost::bind and the preprocessor

From: vesa_karvonen (vesa_karvonen_at_[hidden])
Date: 2002-03-08 08:24:29

--- In boost_at_y..., "Peter Dimov" <pdimov_at_m...> wrote:
[...]
> I haven't found the 'perfect' solution to this problem yet. The
> preprocessor library has the advantage that the preprocessor is
> always present; but it adds a significant amount of obfuscation.

Macro definitions can be a bit difficult to read when they are mixed 
with ordinary C++ code. Macro uses, on the other hand, are not very 
difficult to read. Most of the macros offered by the preprocessor 
library are rather fundamental and should not, IMHO, take a lot of 
time to understand. Take BOOST_PP_REPEAT() for example.

  <--->
  #define BOOST_PP_REPEAT(N,M,P)

  Repeats the macro M(I,P) for I = [0,N[.

  In other words, expands to the sequence:

    M(0,P) M(1,P) ... M(BOOST_PP_DEC(N),P)
  <--->

I don't know how to make this any simpler. BOOST_PP_REPEAT() takes a 
repetition count, a macro to repeat, and an extra parameter. It then 
repeats the macro giving it the index and the extra parameter.

I'll try to find time for PP library during the weekend. There are 
many libraries in Boost that could (not should) use the preprocessor 
library and it is a problem that people find it too difficult to even 
try.