...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
The template class object_pool (see object_pool.html) contains a number of functions construct(..), which both allocate and construct an object in a single operation.
Since the number and type of arguments to this function is totally arbitrary, a simple system has been set up to automatically generate template construct functions. This system is based on the macro preprocessor m4, which is standard on UNIX systems and also available for Win32 systems.
detail/pool_construct.m4, when run with m4, will create the file detail/pool_construct.inc, which only defines the construct functions for the proper number of arguments. The number of arguments may be passed into the file as an m4 macro, NumberOfArguments; if not provided, it will default to 3.
For each different number of arguments (1 to NumberOfArguments), a template function is generated. There are the same number of template parameters as there are arguments, and each argument's type is a reference to that (possibly cv-qualified) template argument. Each possible permutation of the cv-qualifications is also generated.
Because each permutation is generated for each possible number of arguments, the included file size grows exponentially in terms of the number of constructor arguments, not linearly. For the sake of rational compile times, only use as many arguments as you need.
detail/pool_construct.bat and detail/pool_construct.sh are also provided to call m4, defining NumberOfArguments to be their command-line parameter. See these files for more details.
Dependent on for.m4 (see for.html).
This system may be complemented by or replaced by a Python (or some other language) script.
Revised 05 December, 2006
Copyright © 2000, 2001 Stephen Cleary (scleary AT jerviswebb DOT com)
Distributed under the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)