I am declaring a parametric type struct A{L} end, where L should be an integer. For example, in NTuple{N,T}, the N parameter is restricted to be an integer. What is the recommended way to achieve this behavior on my custom time? I could not find the source code of NTuple.

I think that NTuple per se does not check that N is an integer, Vararg (which it is aliased to) does. For structs, the recommended solution is to check in the inner constructor, eg struct A{L} function A{L}() where L @assert L isa Integer new{L}() end end A(L::Integer) = A…

Restrict type of value type parameter

General Usage

Tamas_Papp March 10, 2021, 10:21am 8

It is not clear to me what you are doing (please open a separate topic with an MWE if you need further help). In any case, validating in the constructor is still the recommended method.

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