Complex C declaration

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I haven’t done this in a while!

Start with foo and go right.

float * (*(*foo())[SIZE][SIZE])()

foo is a function with no arguments…

Can’t go right since there’s a closing parenthesis. Go left:

float * (*(* foo())[SIZE][SIZE])()

foo is a function with no arguments returning a pointer

Can’t go left further, so let’s cross the parentheses and go right again

float * (*(* foo())[SIZE][SIZE])()
float * (*(* foo())[SIZE][SIZE])()
float * (*(* foo())[SIZE][SIZE])()

foo is a function with no arguments returning a pointer to an array of SIZE arrays of SIZE …

Closing parenthesis reached, left again to reach a pointer symbol:

float * (*(* foo())[SIZE][SIZE])()

foo is a function with no arguments returning a pointer to an array of SIZE arrays of SIZE pointers to …

Left parenthesis again, so we cross it and go right again:

float *( *(* foo())[SIZE][SIZE])()
float *( *(* foo())[SIZE][SIZE])()

foo is a function with no arguments returning a pointer to an array of SIZE arrays of SIZE pointers to a function with no arguments…

And left to the end

float * ( *(* foo())[SIZE][SIZE])()

foo is a function with no arguments returning a pointer to an array of SIZE arrays of SIZE pointers to a function with no arguments returning a pointer to float

And whoever wrote that, please teach him to use typedef:

// Function that returns a pointer to float
typedef float* PFloatFunc ();

// Array of pointers to PFloatFunc functions
typedef PFloatFunc* PFloatFuncArray2D[SIZE][SIZE];

// Function that returns a pointer to a PFloatFuncArray2D
PFloatFuncArray2D* foo();

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