On Monday, 3 February 2014 at 10:25:19 UTC, Chris wrote:
T[T] attributes;
// ....
public auto getAttribute(T attr) {
if (!(attr in attributes)) {
return null; // Doesn't work for numbers!
}
return attributes[attr];
}
}
One way would be to use std.typecons.Nullable(T) as a return type.
Another would be to retink your design :) Note that for numbers,
there's no distinct "does not exist" value (well, ok, we have NaN
for floating point). Neither there is for structs. Generally such
methods as your getAttribute either throw, or get a second
optional parameter as hint on what to return when the element is
not found in the dictionoary.
