How to ensure the template type is scalar in D? -


i have 2 functions: 1 scalar multiplication vector , other - vector-matrix multiplication:

pure t[] mul(s, t)(s s, t[] a)

and

pure t[] mul(t)(t[] a, t[][] b)

of course leads conflict, s can vector too, first template covers second. how tell compiler, want scalar type s?

you need use template constraint.

pure t[] mul(s, t)(s s, t[] a) if (isscalartype!s)

this declares template should considered when isscalartype!s true.

isscalartype can found in std.traits.

in d, scalar types numeric types, character types, , bool. can restrict further using other traits std.traits if (e.g. isnumeric or isfloatingpoint).


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