Macro: ac_cxx_explicit

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# ac_cxx_explicit

## Synopsis

`AC_CXX_EXPLICIT`

## Version

1.1.1.1 (2001/07/26) C++_Support @ ac-archive-0.5.32

## Author

Luc Maisonobe

## Description

If the compiler can be asked to prevent using implicitly one argument constructors as converting constructors with the explicit keyword, define HAVE_EXPLICIT.

## M4 Source Code

    AC_DEFUN([AC_CXX_EXPLICIT],
    [AC_CACHE_CHECK(whether the compiler supports the explicit keyword,
    ac_cv_cxx_explicit,
    [AC_LANG_SAVE
     AC_LANG_CPLUSPLUS
     AC_TRY_COMPILE([class A{public:explicit A(double){}};],
    [double c = 5.0;A x(c);return 0;],
     ac_cv_cxx_explicit=yes, ac_cv_cxx_explicit=no)
     AC_LANG_RESTORE
    ])
    if test "$ac_cv_cxx_explicit" = yes; then
      AC_DEFINE(HAVE_EXPLICIT,,[define if the compiler supports the explicit keyword])
    fi
    ])