How to convert an int64 to int in Go?

Question

You convert them with a type “conversion”

var a int
var b int64
int64(a) < b

When comparing values, you always want to convert the smaller type to the larger. Converting the other way will possibly truncate the value:

var x int32 = 0
var y int64 = math.MaxInt32 + 1 // y == 2147483648
if x < int32(y) {
// this evaluates to false, because int32(y) is -2147483648

Or in your case to convert the maxInt int64 value to an int, you could use

for a := 2; a < int(maxInt); a++ {

which would fail to execute correctly if maxInt overflows the max value of the int type on your system.