Hi, Just to make sure I understand multidispatch correctly here: There is no way to multidispatch based on a value in a positional argument, correct? For example, something like: function multidispatch(x,y,string_argument) string_argument = "my_string_1" println(x+y) end function multidi…

Well.. It sort of is, for some types. You can use Val to lift a runtime value that’s isbits or of type Symbol to the type domain and dispatch on that in the signature. Things like your String won’t work though. Keep in mind though that this very likely will dispatch dynamically, if the value you’re…

Thanks! With Val, created this example that works correctly: function md2(x,y,new_string::Val{Symbol("prod1")}) new_string println(x+y) end function md2(x,y,new_string::Val{Symbol("prod2")}) new_string println(x/y) end md2(8,4,Val(:prod1)) 12 md2(8,4,Val(:prod2)) 2.0

Another common pattern is to use custom types just for dispatch: julia> struct Prod1 end julia> struct Prod2 end julia> md2(x,y,p::Prod1) = x + y md2 (generic function with 1 method) julia> md2(x,y,p::Prod2) = x * y md2 (generic function with 2 methods) julia> md2(8,4,Prod1()) 12 julia> md2(8,…

And you could even make these into callable structs to cut down notation a bit (if that is appropriate in the OP’s situation, of course)

Multidispatch based on value of positional argument

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Multidispatch based on value of positional argument

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