Hello everyone. I think there’s somebody raising the question in the past but since there’s no news or recent development then, I would like to talk about it again. Julia has the infix operator in and its equivalence ∈. The language also support the reverse, which is ∉, but by my understanding, th…

I don’t think there is much want for an infix ascii \notin. Julia allows you to pick your favourite of two “styles”, traditional ascii, !(a in b); or mathematical a ∉ b, and that’s good enough for most people. It seems like your proposal falls in between these two styles. Personally, I’d encourag…

Thanks for replying. Yes, of course I know how to type and use Unicode inputs by using \ and <tab> , but that doesn’t stop myself from asking why the language supports so many mathematics operators even like ∋ or ∌ but not a simple negation infix to pair with in . Please don’t get me wrong, I’ll hap…

[image] nvhoang.3110: but not a simple negation infix to pair with in Because that’d require having a new reserved keyword in the parser, for limited benefits. The ASCII version of logical negotiation (!) has always been there and it’s not going anywhere.

I suppose a Julian version of not in would be !in. That doesn’t work, but when typed before another method, it seems to make a method that can’t be called? What even is going on here: julia> 3 in [3] true julia> 3 !in [3] ERROR: syntax: extra token "!" after end of expression julia> in in (generic…

[image] Benny: it seems to make a method that can’t be called? What even is going on here: !(f::Function) = (x...)->!f(x...) julia> !in([1,2,3], 4) true It may be called as a normal function, just not as an infix.

Seems like !in([1,2,3], 4) still parses as in then ! separately. Parentheses can help call the actual !in: julia> @which !in([1,2,3], 4) !(x::Bool) in Base at bool.jl:35 julia> @which (!in)([1,2,3], 4) (::Base.var"#84#85")(x...) in Base at operators.jl:1117 So I suppose the intention is to create…

[image] Jollywatt: I don’t think there is much want for an infix ascii \notin Well, I certainly disagree with that statement: ! for infix operators · Issue #25512 · JuliaLang/julia · GitHub (and the request received some support.) I would very much like to be able to write a !in B, but there…

Thanks for replying. Then I would agree with what @Benny and @jishnub said, as the version of not in should be !in, but it just doesn’t work like that. By adding the parenthesis, it becomes a normal function, not an infix anymore.

Julia's infix as synonym for ∉ operator?

New to Julia

DNF June 16, 2022, 9:20am 10

More discussion here: ! for infix operators and Add infix "!in" as synonym for ∉ ? · Issue #15353 · JuliaLang/julia · GitHub

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Julia's infix as synonym for ∉ operator?

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