Assertions

Assertions in programming languages such as #c, #cpp and #rust are used as a mean of comparing the output of a function or method of a class to the expected value. They can be incorporated well into the test facility like Rust.

In C and C++, the keywords assert and _assert are usually viewed as a Debugging Tools. However, as recommended by Hunt et al., if you ever feel that #something can’t happen, it is a great opportunity to ensure it won’t by using assertions. Even though assertions can add overhead to the program, turning them off when building the binary is a bad idea since it assumes tests alone would find every bug in the codebase which is not the case.

Note: Never put code that must be executed into assertions as it might be turned off by some pricks.

Note: Avoid side effects in assertions at all costs.

Don’t use assertions as a mean of error handling! The difference between the two is the former checks things that must not happen, the latter checks things that could happen.

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The Pragmatic Programmer

If there is something that surprise you, reevaluate your assumptions. Don’t just “know” your code works, prove it, in this context, with this data, with these boundary conditions. Add new test# to it, 202207091736# or put some 202207091744#.
Refactoring: Improving The Design of Existing Code

Comment# are usually an indicator for refactoring. If there’s a need to explain what a code does, extract it as a new method with easily understandable name (or rename it if it already exists). If the comments are used to state rules, use Assertions# to enforce it.
Locate a Bug

202207091744# (useful on preconditions, post conditions and invariants)
“It Can’t Happen”

If, for example, you have stumbling across the application codebase, run it, and found something that surprise you, reevaluate your assumptions, be willing to debug it#. Don’t just “know” your code works, prove it, in this context, with this data, with these boundary conditions. Add new test# to it, Crash Program Earlier# or put some Assertions#. You can go further by adopting Defensive Programming#, enforcing checks on precondition, postcondition and class invariant by Design by Contract (DBC)#.

#debugging #oop #functional-programming #c #cpp #rust