mfbt/MacroForEach.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 /*
   8  * Implements a higher-order macro for iteratively calling another macro with
   9  * fixed leading arguments, plus a trailing element picked from a second list
  10  * of arguments.
  11  */
  12
  13 #ifndef mozilla_MacroForEach_h
  14 #define mozilla_MacroForEach_h
  15
  16 #include "mozilla/MacroArgs.h"
  17
  18 /*
  19  * MOZ_FOR_EACH(aMacro, aFixedArgs, aArgs) expands to N calls to the macro
  20  * |aMacro| where N is equal the number of items in the list |aArgs|. The
  21  * arguments for each |aMacro| call are composed of *all* arguments in the list
  22  * |aFixedArgs| as well as a single argument in the list |aArgs|. For example:
  23  *
  24  *   #define MACRO_A(x) x +
  25  *   int a = MOZ_FOR_EACH(MACRO_A, (), (1, 2, 3)) 0;
  26  *   // Expands to:     MACRO_A(1) MACRO_A(2) MACRO_A(3) 0;
  27  *   // And further to: 1 + 2 + 3 + 0;
  28  *
  29  *   #define MACRO_B(k, x) (k + x) +
  30  *   int b = MOZ_FOR_EACH(MACRO_B, (5,), (1, 2)) 0;
  31  *   // Expands to: MACRO_B(5, 1) MACRO_B(5, 2) 0;
  32  *
  33  *   #define MACRO_C(k1, k2, x) (k1 + k2 + x) +
  34  *   int c = MOZ_FOR_EACH(MACRO_C, (5, 8,), (1, 2)) 0;
  35  *   // Expands to: MACRO_B(5, 8, 1) MACRO_B(5, 8, 2) 0;
  36  *
  37  * MOZ_FOR_EACH_SEPARATED(aMacro, aSeparator, aFixedArgs, aArgs) is identical
  38  * to MOZ_FOR_EACH except that it inserts |aSeparator| between each call to
  39  * the macro. |aSeparator| must be wrapped by parens. For example:
  40  *
  41  *   #define MACRO_A(x) x
  42  *   int a = MOZ_FOR_EACH_SEPARATED(MACRO_A, (+), (), (1, 2, 3));
  43  *   // Expands to: MACRO_A(1) + MACRO_A(2) + MACRO_A(3);
  44  *   // And further to: 1 + 2 + 3
  45  *
  46  *   #define MACRO_B(t, n) t n
  47  *   void test(MOZ_FOR_EACH_SEPARATED(MACRO_B, (,), (int,), (a, b)));
  48  *   // Expands to: void test(MACRO_B(int, a) , MACRO_B(int, b));
  49  *   // And further to: void test(int a , int b);
  50  *
  51  * If the |aFixedArgs| list is not empty, a trailing comma must be included.
  52  *
  53  * The |aArgs| list may be up to 50 items long.
  54  */
  55 #define MOZ_FOR_EACH_EXPAND_HELPER(...) __VA_ARGS__
  56 #define MOZ_FOR_EACH_GLUE(a, b) a b
  57 #define MOZ_FOR_EACH_SEPARATED(aMacro, aSeparator, aFixedArgs, aArgs)     \
  58   MOZ_FOR_EACH_GLUE(MOZ_PASTE_PREFIX_AND_ARG_COUNT(                       \
  59                         MOZ_FOR_EACH_, MOZ_FOR_EACH_EXPAND_HELPER aArgs), \
  60                     (aMacro, aSeparator, aFixedArgs, aArgs))
  61 #define MOZ_FOR_EACH(aMacro, aFixedArgs, aArgs) \
  62   MOZ_FOR_EACH_SEPARATED(aMacro, (), aFixedArgs, aArgs)
  63
  64 #define MOZ_FOR_EACH_HELPER_GLUE(a, b) a b
  65 #define MOZ_FOR_EACH_HELPER(aMacro, aFixedArgs, aArgs) \
  66   MOZ_FOR_EACH_HELPER_GLUE(                            \
  67       aMacro, (MOZ_FOR_EACH_EXPAND_HELPER aFixedArgs MOZ_ARG_1 aArgs))
  68
  69 #define MOZ_FOR_EACH_0(m, s, fa, a)
  70 #define MOZ_FOR_EACH_1(m, s, fa, a) MOZ_FOR_EACH_HELPER(m, fa, a)
  71 #define MOZ_FOR_EACH_2(m, s, fa, a) \
  72   MOZ_FOR_EACH_HELPER(m, fa, a)     \
  73   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_1(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  74 #define MOZ_FOR_EACH_3(m, s, fa, a) \
  75   MOZ_FOR_EACH_HELPER(m, fa, a)     \
  76   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_2(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  77 #define MOZ_FOR_EACH_4(m, s, fa, a) \
  78   MOZ_FOR_EACH_HELPER(m, fa, a)     \
  79   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_3(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  80 #define MOZ_FOR_EACH_5(m, s, fa, a) \
  81   MOZ_FOR_EACH_HELPER(m, fa, a)     \
  82   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_4(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  83 #define MOZ_FOR_EACH_6(m, s, fa, a) \
  84   MOZ_FOR_EACH_HELPER(m, fa, a)     \
  85   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_5(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  86 #define MOZ_FOR_EACH_7(m, s, fa, a) \
  87   MOZ_FOR_EACH_HELPER(m, fa, a)     \
  88   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_6(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  89 #define MOZ_FOR_EACH_8(m, s, fa, a) \
  90   MOZ_FOR_EACH_HELPER(m, fa, a)     \
  91   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_7(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  92 #define MOZ_FOR_EACH_9(m, s, fa, a) \
  93   MOZ_FOR_EACH_HELPER(m, fa, a)     \
  94   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_8(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  95 #define MOZ_FOR_EACH_10(m, s, fa, a) \
  96   MOZ_FOR_EACH_HELPER(m, fa, a)      \
  97   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_9(m, s, fa, (MOZ_ARGS_AFTER_1 a))
  98 #define MOZ_FOR_EACH_11(m, s, fa, a) \
  99   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 100   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_10(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 101 #define MOZ_FOR_EACH_12(m, s, fa, a) \
 102   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 103   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_11(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 104 #define MOZ_FOR_EACH_13(m, s, fa, a) \
 105   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 106   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_12(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 107 #define MOZ_FOR_EACH_14(m, s, fa, a) \
 108   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 109   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_13(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 110 #define MOZ_FOR_EACH_15(m, s, fa, a) \
 111   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 112   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_14(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 113 #define MOZ_FOR_EACH_16(m, s, fa, a) \
 114   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 115   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_15(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 116 #define MOZ_FOR_EACH_17(m, s, fa, a) \
 117   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 118   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_16(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 119 #define MOZ_FOR_EACH_18(m, s, fa, a) \
 120   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 121   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_17(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 122 #define MOZ_FOR_EACH_19(m, s, fa, a) \
 123   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 124   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_18(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 125 #define MOZ_FOR_EACH_20(m, s, fa, a) \
 126   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 127   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_19(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 128 #define MOZ_FOR_EACH_21(m, s, fa, a) \
 129   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 130   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_20(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 131 #define MOZ_FOR_EACH_22(m, s, fa, a) \
 132   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 133   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_21(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 134 #define MOZ_FOR_EACH_23(m, s, fa, a) \
 135   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 136   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_22(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 137 #define MOZ_FOR_EACH_24(m, s, fa, a) \
 138   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 139   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_23(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 140 #define MOZ_FOR_EACH_25(m, s, fa, a) \
 141   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 142   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_24(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 143 #define MOZ_FOR_EACH_26(m, s, fa, a) \
 144   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 145   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_25(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 146 #define MOZ_FOR_EACH_27(m, s, fa, a) \
 147   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 148   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_26(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 149 #define MOZ_FOR_EACH_28(m, s, fa, a) \
 150   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 151   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_27(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 152 #define MOZ_FOR_EACH_29(m, s, fa, a) \
 153   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 154   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_28(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 155 #define MOZ_FOR_EACH_30(m, s, fa, a) \
 156   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 157   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_29(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 158 #define MOZ_FOR_EACH_31(m, s, fa, a) \
 159   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 160   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_30(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 161 #define MOZ_FOR_EACH_32(m, s, fa, a) \
 162   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 163   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_31(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 164 #define MOZ_FOR_EACH_33(m, s, fa, a) \
 165   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 166   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_32(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 167 #define MOZ_FOR_EACH_34(m, s, fa, a) \
 168   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 169   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_33(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 170 #define MOZ_FOR_EACH_35(m, s, fa, a) \
 171   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 172   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_34(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 173 #define MOZ_FOR_EACH_36(m, s, fa, a) \
 174   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 175   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_35(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 176 #define MOZ_FOR_EACH_37(m, s, fa, a) \
 177   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 178   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_36(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 179 #define MOZ_FOR_EACH_38(m, s, fa, a) \
 180   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 181   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_37(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 182 #define MOZ_FOR_EACH_39(m, s, fa, a) \
 183   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 184   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_38(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 185 #define MOZ_FOR_EACH_40(m, s, fa, a) \
 186   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 187   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_39(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 188 #define MOZ_FOR_EACH_41(m, s, fa, a) \
 189   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 190   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_40(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 191 #define MOZ_FOR_EACH_42(m, s, fa, a) \
 192   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 193   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_41(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 194 #define MOZ_FOR_EACH_43(m, s, fa, a) \
 195   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 196   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_42(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 197 #define MOZ_FOR_EACH_44(m, s, fa, a) \
 198   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 199   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_43(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 200 #define MOZ_FOR_EACH_45(m, s, fa, a) \
 201   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 202   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_44(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 203 #define MOZ_FOR_EACH_46(m, s, fa, a) \
 204   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 205   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_45(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 206 #define MOZ_FOR_EACH_47(m, s, fa, a) \
 207   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 208   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_46(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 209 #define MOZ_FOR_EACH_48(m, s, fa, a) \
 210   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 211   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_47(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 212 #define MOZ_FOR_EACH_49(m, s, fa, a) \
 213   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 214   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_48(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 215 #define MOZ_FOR_EACH_50(m, s, fa, a) \
 216   MOZ_FOR_EACH_HELPER(m, fa, a)      \
 217   MOZ_FOR_EACH_EXPAND_HELPER s MOZ_FOR_EACH_49(m, s, fa, (MOZ_ARGS_AFTER_1 a))
 218
 219 #endif /* mozilla_MacroForEach_h */