https://issues.dlang.org/show_bug.cgi?id=19686
Issue ID: 19686
Summary: sgn is too greedy
Product: D
Version: D2
Hardware: x86
OS: Windows
Status: NEW
Severity: enhancement
Priority: P1
Component: phobos
Assignee: [email protected]
Reporter: [email protected]
The current implementation of sgn in Phobos is too greedy, and will match types
that it doesn't work with. For reference, this is what sgn look like at time of
writing:
F sgn(F)(F x) @safe pure nothrow @nogc
{
// @@@TODO@@@: make this faster
return x > 0 ? 1 : x < 0 ? -1 : x;
}
This greedyness leads to error messages with template spam when doing things
like sgn("string"), and also makes it misbehave when used alongside other sgns
for other types (e.g. std.complex).
It should look more like this:
F sgn(F)(F x) @safe pure nothrow @nogc
if (isFloatingPoint!F || isIntegral!F)
{
// @@@TODO@@@: make this faster
return x > 0 ? 1 : x < 0 ? -1 : x;
}
--
