1 /************************************************************** 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, 14 * software distributed under the License is distributed on an 15 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 16 * KIND, either express or implied. See the License for the 17 * specific language governing permissions and limitations 18 * under the License. 19 * 20 *************************************************************/ 21 22 23 24 /* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil -*- */ 25 #ifndef WW_NEEDED_CAST_HXX 26 #define WW_NEEDED_CAST_HXX 27 28 #include <tools/debug.hxx> 29 # include "staticassert.hxx" 30 31 namespace ww 32 { checking_cast(Param in,Ret)33 template<typename Ret, typename Param> Ret checking_cast(Param in, Ret) 34 { 35 return static_cast<Ret>(in); 36 } 37 checking_cast(Ret in,Ret)38 template<typename Ret> Ret checking_cast(Ret in, Ret) 39 { 40 DBG_ASSERT( false, "UnnecessaryCast" ); 41 return in; 42 } 43 44 /* 45 needed_cast is the same as static_cast except that there will be a compile 46 time assert when NDEBUG is not defined and the in and out types are the 47 same. i.e. needed_cast catches unneccessary casts 48 */ needed_cast(Param in)49 template<typename Ret, typename Param> Ret needed_cast(Param in) 50 { 51 /* 52 Massage a single argument and a ret value into two arguments to allow 53 a determination if the dest type is the same as the sourct type 54 */ 55 return checking_cast(in, Ret()); 56 } 57 } 58 #endif 59 /* vi:set tabstop=4 shiftwidth=4 expandtab: */ 60