Apparently, it’s currently impossible to extend builtin functions. Is there an effort to change this? Or is there a way around the restriction already? The issue came up in a feature request for NumberIntervals.jl .

No it doesn’t make much sense to allow that. What makes sense is to change it to a normal function with a default implementation using a builtin function if overloading is desired. For ifelse, it’s pretty much an eager ?: and should probably be implemented like that.

That’s ok, I’m really only interested in extending ifelse() for a three-value logic usecase. Should I open an issue for that in the Julia github?

For reference make `ifelse` generic · Issue #32844 · JuliaLang/julia · GitHub

Extending builtin functions like ifelse()

General Usage

yuyichao August 8, 2019, 8:11pm 4

You can open one about removing the ifelse builtin and replacing it with a branch if you want.

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Extending builtin functions like ifelse()

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