Assertions are statements used to test assumptions made by programmer. For example, we may use assertion to check if pointer returned by malloc() is NULL or not.
Following is syntax for assertion.
void assert( int expression );
If expression evaluates to 0 (false), then the expression, sourcecode filename, and line number are sent to the standard error, and then abort() function is called.
For example, consider the following program.
Assertion failed: x==7, file test.cpp, line 13 This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information.
Assertion Vs Normal Error Handling
Assertions are mainly used to check logically impossible situations. For example, they can be used to check the state a code expects before it starts running or state after it finishes running. Unlike normal error handling, assertions are generally disabled at run-time. Therefore, it is not a good idea to write statements in asser() that can cause side effects. For example writing something like assert(x = 5) is not a good ideas as x is changed and this change won’t happen when assertions are disabled. See this for more details.
In C/C++, we can completely remove assertions at compile time using the preprocessor NODEBUG.
The above program compiles and runs fine.
In Java, assertions are not enabled by default and we must pass an option to run-time engine to enable them.
Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.
- How to flatten a Vector of Vectors or 2D Vector in C++
- <complex.h> header file in C with Examples
- Remove odd frequency characters from the string
- Different ways to use Const with Reference to a Pointer in C++
- std::to_address in C++ with Examples
- Program to create Custom Vector Class in C++
- std::is_trivially_copy_constructible in C/C++
- Difference between Python and C++
- tgamma() method in C/C++ with Examples
- boost::type_traits::is_array Template in C++
- boost is_pointer template in C++
- Modulo Operator (%) in C/C++ with Examples
- fpclassify() method in C/C++ with Examples
- Operator Overloading '<<' and '>>' operator in a linked list class
Improved By : Jaideep Kaiwart