mbed_preprocessor.h

00001 /** \addtogroup platform */
00002 /** @{*/
00003 /**
00004  * \defgroup platform_preprocessor preprocessor macros
00005  * @{
00006  */
00007 
00008 /* mbed Microcontroller Library
00009  * Copyright (c) 2006-2013 ARM Limited
00010  *
00011  * Licensed under the Apache License, Version 2.0 (the "License");
00012  * you may not use this file except in compliance with the License.
00013  * You may obtain a copy of the License at
00014  *
00015  *     http://www.apache.org/licenses/LICENSE-2.0
00016  *
00017  * Unless required by applicable law or agreed to in writing, software
00018  * distributed under the License is distributed on an "AS IS" BASIS,
00019  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00020  * See the License for the specific language governing permissions and
00021  * limitations under the License.
00022  */
00023 #ifndef MBED_PREPROCESSOR_H
00024 #define MBED_PREPROCESSOR_H
00025 
00026 
00027 /** MBED_CONCAT
00028  *  Concatenate tokens together
00029  *
00030  *  @note
00031  *  Expands tokens before concatenation
00032  *
00033  *  @code
00034  *  // Creates a unique label based on the line number
00035  *  int MBED_CONCAT(UNIQUE_LABEL_, __LINE__) = 1;
00036  *  @endcode
00037  */
00038 #define MBED_CONCAT(a, b) MBED_CONCAT_(a, b)
00039 #define MBED_CONCAT_(a, b) a##b
00040 
00041 /** MBED_STRINGIFY
00042  *  Converts tokens into strings
00043  *
00044  *  @note
00045  *  Expands tokens before stringification
00046  *
00047  *  @code
00048  *  // Creates a string based on the parameters
00049  *  const char *c = MBED_STRINGIFY(This is a ridiculous way to create a string)
00050  *  @endcode
00051  */
00052 #define MBED_STRINGIFY(a) MBED_STRINGIFY_(a)
00053 #define MBED_STRINGIFY_(a) #a
00054 
00055 /** MBED_STRLEN
00056  *  Reports string token length
00057  *
00058  *  @note
00059  *  Expands tokens before calculating length
00060  *
00061  *  @code
00062  *  // Get string length
00063  *  const int len = MBED_STRLEN("Get the length")
00064  *  @endcode
00065  */
00066 #define MBED_STRLEN(a) MBED_STRLEN_(a)
00067 #define MBED_STRLEN_(a) (sizeof(a) - 1)
00068 
00069 /** MBED_COUNT_VA_ARGS(...)
00070  *  Reports number of tokens passed
00071  *
00072  *  @note
00073  *  Token limit is 16
00074  *
00075  *  @code
00076  *  // Get number of arguments
00077  *  const int count = MBED_COUNT_VA_ARGS("Address 0x%x, Data[0] = %d Data[1] = %d", 0x20001234, 10, 20)
00078  *  @endcode
00079  */
00080 #define MBED_COUNT_VA_ARGS(...) GET_NTH_ARG_(__VA_ARGS__, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1)
00081 #define GET_NTH_ARG_(_1, _2, _3, _4, _5, _6, _7, _8, _9, _10, _11, _12, _13, _14, _15, N, ...) N
00082 
00083 #endif
00084 
00085 /** @}*/
00086 /** @}*/