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Longer macro parameter names

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[SVN r13459]
This commit is contained in:
Vesa Karvonen
2002-04-12 11:26:25 +00:00
parent 3468956bc9
commit 06ff87a86c
96 changed files with 368 additions and 322 deletions
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22
include/boost/preprocessor/while.hpp
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@ -16,22 +16,22 @@
#include <boost/preprocessor/if.hpp>
#include <boost/preprocessor/tuple/eat.hpp>
/** <p>Iterates <code>F(D,X)</code> while <code>C(D,X)</code> is true.</p>
/** <p>Iterates <code>OP(D,STATE)</code> while <code>PRED(D,STATE)</code> is true.</p>
<p>In other words, expands to:</p>
<pre>
F(D, ... F(D, F(D,X) ) ... )
OP(D, ... OP(D, OP(D,STATE) ) ... )
</pre>
<p>The depth of iteration is determined by <code>C(D,X)</code>.</p>
<p>The depth of iteration is determined by <code>PRED(D,STATE)</code>.</p>
<p>For example,</p>
<pre>
#define C(D,X) BOOST_PP_LESS_D(D,BOOST_PP_TUPLE_ELEM(2,0,X),BOOST_PP_TUPLE_ELEM(2,1,X))
#define F(D,X) (BOOST_PP_INC(BOOST_PP_TUPLE_ELEM(2,0,X)),BOOST_PP_TUPLE_ELEM(2,1,X))
BOOST_PP_WHILE(C,F,(0,3))
#define PRED(D,STATE) BOOST_PP_LESS_D(D,BOOST_PP_TUPLE_ELEM(2,0,STATE),BOOST_PP_TUPLE_ELEM(2,1,STATE))
#define OP(D,STATE) (BOOST_PP_INC(BOOST_PP_TUPLE_ELEM(2,0,STATE)),BOOST_PP_TUPLE_ELEM(2,1,STATE))
BOOST_PP_WHILE(PRED,OP,(0,3))
</pre>
<p>expands to:</p>
@ -42,11 +42,11 @@
<h3>Legend</h3>
<ul>
<li><b>X</b> is the current state of iteration. The state is usually a tuple.</li>
<li><b>C</b> is the condition for iteration. It must expand to a decimal
<li><b>STATE</b> is the current state of iteration. The state is usually a tuple.</li>
<li><b>PRED</b> is the condition for iteration. It must expand to a decimal
integer literal.</li>
<li><b>F</b> is the iterated macro. Note that if the state is a tuple, then
F(D,X) usually expands to a tuple of the same number of elements.</li>
<li><b>OP</b> is the iterated macro. Note that if the state is a tuple, then
OP(D,STATE) usually expands to a tuple of the same number of elements.</li>
<li><b>D</b> is the recursion depth and should only be used as a parameter
to other macros using BOOST_PP_WHILE(). Such macros include
BOOST_PP_ADD() and other arithmetic operations. For each macro using
@ -73,7 +73,7 @@
<li><a href="../../example/delay.c">delay.c</a></li>
</ul>
*/
#define BOOST_PP_WHILE(C,F,X) BOOST_PP_WHILE_C(C(1,X),0,X)(C,F,F(1,X))
#define BOOST_PP_WHILE(PRED,OP,STATE) BOOST_PP_WHILE_C(PRED(1,STATE),0,STATE)(PRED,OP,OP(1,STATE))
#define BOOST_PP_WHILE_C(C,D,X) BOOST_PP_IF(C,BOOST_PP_WHILE##D,X BOOST_PP_TUPLE3_EAT)
#define BOOST_PP_WHILE0(C,F,X) BOOST_PP_WHILE_C(C(2,X),1,X)(C,F,F(2,X))