muls

Multiply two signed integers, checking for overflow.

The overflow is sticky, meaning a sequence of operations can be done and overflow need only be checked at the end.

int muls(int x, int y, bool overflow)
long muls(long x, long y, bool overflow)
cent muls(cent x, cent y, bool overflow)
nothrow @safe @nogc pure pragma(inline, true)
static if(is(cent))
cent
muls
()
(
cent x
,
cent y
,
ref bool overflow
)

Parameters

x cent: left operand
y cent: right operand
overflow bool: set if an overflow occurs, is not affected otherwise

Return Value

Type: cent

the product

Examples

bool overflow;
assert(muls(2, 3, overflow) == 6);
assert(!overflow);

assert(muls(-200, 300, overflow) == -60_000);
assert(!overflow);

assert(muls(1, int.max, overflow) == int.max);
assert(!overflow);

assert(muls(int.min, 1, overflow) == int.min);
assert(!overflow);

assert(muls(int.max, 2, overflow) == (int.max * 2));
assert(overflow);

overflow = false;
assert(muls(int.min, -1, overflow) == int.min);
assert(overflow);

assert(muls(0, 0, overflow) == 0);
assert(overflow);                   // sticky

bool overflow;
assert(muls(2L, 3L, overflow) == 6);
assert(!overflow);

assert(muls(-200L, 300L, overflow) == -60_000);
assert(!overflow);

assert(muls(1, long.max, overflow) == long.max);
assert(!overflow);

assert(muls(long.min, 1L, overflow) == long.min);
assert(!overflow);

assert(muls(long.max, 2L, overflow) == (long.max * 2));
assert(overflow);
overflow = false;

assert(muls(-1L, long.min, overflow) == long.min);
assert(overflow);

overflow = false;
assert(muls(long.min, -1L, overflow) == long.min);
assert(overflow);

assert(muls(0L, 0L, overflow) == 0);
assert(overflow);                   // sticky

muls

Parameters

Return Value

Examples

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