Question

Why isn’t it in C (or C++) allowed?

I mean this:

ucell GetPlayerPosPositionData[5];
GetPlayerPosPositionData = {4*sizeof(cell),playerid,0,sizeof(cell),2*sizeof(cell)};//this does not work, error

//normal assignment
GetPlayerPosPositionData[1] = playerid;
GetPlayerPosPositionData[2] = 0;
GetPlayerPosPositionData[3] = sizeof(cell);
GetPlayerPosPositionData[4] = 2*sizeof(cell);

Answer 1

Because the syntax says it is not allowed? There are two parts to the problem:

1. You can’t use the initializer syntax except in an initializer or (in C99) in a compound literal.

2. You can’t assign whole arrays.

In C99, you could pass an array to a function:

typedef unsigned int cell;

extern void some_func(cell data[]);

extern void func(void);

void func(void)
{
    cell playerid = 0;
    some_func((cell[]){4*sizeof(cell),playerid,0,sizeof(cell),2*sizeof(cell)});
}

(Your question is unclear on cell vs ucell; I chose to use cell throughout.)

You still can’t do array assignment. If the array is wrapped in a structure, you can do the structure assignment which, coincidentally, assigns the contained array. But that is a structure assignment, not an array assignment.