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Documentation terminology corrected: function -> macro

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[SVN r12363]
This commit is contained in:
Vesa Karvonen
2002-01-19 20:22:43 +00:00
parent 03e35a4408
commit 7653a0a42a
1 changed files with 9 additions and 9 deletions
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18
include/boost/preprocessor/while.hpp
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@ -29,13 +29,13 @@
<B>C</B> is the condition for iteration. It must expand to a decimal integer <B>C</B> is the condition for iteration. It must expand to a decimal integer
literal. literal.
<B>F</B> is the iterated function. Note that if the state is a tuple, then <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. F(D,X) usually expands to a tuple of the same number of elements.
<B>D</B> is the recursion depth and should only be used as a parameter to <B>D</B> is the recursion depth and should only be used as a parameter to
other functions implemented using BOOST_PP_WHILE(). Such functions include other macros implemented using BOOST_PP_WHILE(). Such macros include
BOOST_PP_ADD() and other arithmetic operations. For each function implemented BOOST_PP_ADD() and other arithmetic operations. For each macro implemented
using BOOST_PP_WHILE(), there is a version of the function, distinguished by using BOOST_PP_WHILE(), there is a version of the macro, distinguished by
the _D suffix (e.g. BOOST_PP_ADD_D()), that accepts an additional recursion the _D suffix (e.g. BOOST_PP_ADD_D()), that accepts an additional recursion
depth as the first parameter. This technique is necessary to avoid depth as the first parameter. This technique is necessary to avoid
recursively expanding the same macro again, which is not permitted by the recursively expanding the same macro again, which is not permitted by the
@ -55,13 +55,13 @@ expanding to a 0:
<PRE>\verbatim <PRE>\verbatim
#define COUNT_DOWN(N) BOOST_PP_WHILE(COUNT_DOWN_C,COUNT_DOWN_F,N) #define COUNT_DOWN(N) BOOST_PP_WHILE(COUNT_DOWN_C,COUNT_DOWN_F,N)
// Above is the function we are implementing using BOOST_PP_WHILE(). // Above is the macro we are implementing using BOOST_PP_WHILE().
#define COUNT_DOWN_C(D,N) N #define COUNT_DOWN_C(D,N) N
// Above is the Condition. It expands to the current N. // Above is the condition. It expands to the current N.
#define COUNT_DOWN_F(D,N) BOOST_PP_DEC(N) #define COUNT_DOWN_F(D,N) BOOST_PP_DEC(N)
// Above is the iteration Function. It decrements N. // Above is the iteration macro. It decrements N.
COUNT_DOWN(50) COUNT_DOWN(50)
// The above expands to 0. // The above expands to 0.
@ -72,7 +72,7 @@ BOOST_PP_MUL().
<PRE>\verbatim <PRE>\verbatim
#define BOOST_PP_MUL(X,Y) BOOST_PP_MUL_D(0,X,Y) #define BOOST_PP_MUL(X,Y) BOOST_PP_MUL_D(0,X,Y)
// Since the function is implemented using WHILE, the actual implementation // Since the macro is implemented using WHILE, the actual implementation
// takes a depth as a parameter so that it can be called inside a WHILE. // takes a depth as a parameter so that it can be called inside a WHILE.
// The above easy-to-use version simply uses 0 as the depth and can not be // The above easy-to-use version simply uses 0 as the depth and can not be
// called inside a WHILE. // called inside a WHILE.
@ -88,7 +88,7 @@ BOOST_PP_MUL().
// #2) The WHILE primitive is "invoked" directly. BOOST_PP_WHILE(D,...) // #2) The WHILE primitive is "invoked" directly. BOOST_PP_WHILE(D,...)
// can't be used because it would not be expanded by the C preprocessor. // can't be used because it would not be expanded by the C preprocessor.
// //
// #3) ???_C is the condition and ???_F is the iteration function. // #3) ???_C is the condition and ???_F is the iteration macro.
#define BOOST_PP_MUL_C(D,P)\ #define BOOST_PP_MUL_C(D,P)\
BOOST_PP_TUPLE_ELEM(3,2,P) BOOST_PP_TUPLE_ELEM(3,2,P)