How do I set a UInt32 to it's maximum value

Question

1. What is the maximum value for a UInt32?

2. Is there a way I can use the sizeof operator to get the maximum value (as it is unsigned)? So I don't end up with #defines or magic numbers in my code.

Answer 1

There's a macro UINT32_MAX defined in stdint.h which you can use

#include <stdint.h>

uint32_t max = UINT32_MAX;

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More about the relevant header <stdint.h>:

http://pubs.opengroup.org/onlinepubs/009695299/basedefs/stdint.h.html

Answer 2

The maximum value for UInt32 is 0xFFFFFFFF (or 4294967295 in decimal).

sizeof(UInt32) would not return the maximum value; it would return 4, the size in bytes of a 32 bit unsigned integer.

Answer 3

Just set the max using standard hexadecimal notation and then check it against whatever you need. 32-bits is 8 hexadecimals bytes, so it'd be like this:

let myMax: UInt32 = 0xFFFFFFFF

if myOtherNumber > myMax {
    // resolve problem
}

Answer 4

The portable way:

std::numeric_limits<uint32_t>::max()