clang/test/Preprocessor/macro_vaopt_p1042r1.cpp

   1  RUN: %clang_cc1 -E %s -pedantic -std=c++2a | FileCheck -strict-whitespace %s
   2
   3 #define LPAREN() (
   4 #define G(Q) 42
   5 #define F1(R, X, ...)  __VA_OPT__(G R X) )
   6 1: int x = F1(LPAREN(), 0, <:-);
   7 // CHECK: 1: int x = 42;
   8
   9 #define F2(...) f(0 __VA_OPT__(,) __VA_ARGS__)
  10 #define EMP
  11 2: F2(EMP)
  12 // CHECK: 2: f(0 )
  13
  14 #define H3(X, ...) #__VA_OPT__(X##X X##X)
  15 3: H3(, 0)
  16 // CHECK: 3: ""
  17
  18 #define H4(X, ...) __VA_OPT__(a X ## X) ## b
  19 4: H4(, 1)
  20 // CHECK: 4: a b
  21
  22 #define H4B(X, ...) a ## __VA_OPT__(X ## X b)
  23 4B: H4B(, 1)
  24 // CHECK: 4B: a b
  25
  26 #define H5A(...) __VA_OPT__()/**/__VA_OPT__()
  27 #define H5B(X) a ## X ## b
  28 #define H5C(X) H5B(X)
  29 5: H5C(H5A())
  30 // CHECK: 5: ab