The ``Clockwise/Spiral Rule''
By David Anderson
There is a technique known as the ``Clockwise/Spiral Rule'' which enables any C programmer to parse in their head any C declaration!
There are three simple steps to follow:
Starting with the unknown element, move in a spiral/clockwise direction; when ecountering the following elements replace them with the corresponding english statements: [X] or [] => Array X size of... or Array undefined size of... (type1, type2) => function passing type1 and type2 returning... * => pointer(s) to... Keep doing this in a spiral/clockwise direction until all tokens have been covered. Always resolve anything in parenthesis first!
Example #1: Simple declaration
+-------+ | +-+ | | ^ | | char *str[10]; ^ ^ | | | +---+ | +-----------+
``str is an...
We move in a spiral clockwise direction starting with `str' and the first character we see is a `[' so, that means we have an array, so... ``str is an array 10 of...
Continue in a spiral clockwise direction, and the next thing we encounter is the `*' so, that means we have pointers, so... ``str is an array 10 of pointers to...
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