Why Can't We Pass Arrays by Value in Functions?

Array Value-Passing Anomaly in Functions

Despite the ability to pass complex class instances to functions, passing arrays by value remains puzzling. Why is this the case?

Historical Roots

The underlying reason is historical. The simplified rule, "arrays decay into pointers when passed to a function," has persisted as a convenient solution to handling arrays in functions.

Complexity of Array Copying

Copying arrays would be a cumbersome and potentially unclear process. The behavior would vary depending on parameter types and function declarations.

Indirect Value Passing

While it's not possible to directly pass arrays by value, indirect value passing still allows manipulation of arrays within functions. Consider the following example:

struct A { int arr[2]; };
void func(struct A);

Passing an instance of struct A to func() indirectly passes its array by value. Within the function, the array can be manipulated without altering the original.

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