I tried to list all the ways one can define functions in Julia. Some are practical, some are silly but collecting them all is fun. Planning to make a video for fun exploring this. function name(a, b) a + b end name(a,b) = a + b if false name = (a,b) -> a+b end name2 = (a,b) -> a+b nam…

Huh, interesting. I would have expected where to be a reserved word in Julia, or at least throw some kind of warning. On the other hand, one would have to go deliberately out of their way to make that construct, so forbidding it may arguably not be warranted.

wow! Why can I do this: julia> a*b=a+b * (generic function with 1 method) julia> 2*3 5 but not this julia> 2*3 6 julia> a*b=a+b ERROR: error in method definition: function Base.* must be explicitly imported to be extended Stacktrace: [1] top-level scope @ none:0 [2] top-level scope @ RE…

[image] fgerick: Shouldn’t the first one give the same warning? I agree that that in particular could show a warning or an error. But note that this is the behaviour for every function exported by any module: julia> module A export f f(x) = 1 end Main.A julia> using…

Thanks for clarifying, up until now I assumed that your first example would also give an error! That might have caused some confusion in the past :sweat_smile:

Another one, I have not seen yet julia> name1 = begin x y=2 end -> x + y #1 (generic function with 1 method) julia> name1(1) 3 julia> name1(2;y=2) 4 julia> name2 = begin x y end -> x + y #4 (generic function with 1 method) julia> name2(2…

Why is begin; x; y; end equivalent to (x;y) in this context?

I am not too sure but I would say that multiple unrelated expressions are parsed as a block so (x;y) is a valid block. You can then replace (x;y) by begin; x; y; end in the function declaration. julia> :((x;y)) |> dump Expr head: Symbol block args: Array{Any}((3,)) 1: Symbol x 2: LineNu…

Finally published this as an article after much procrastination [image] There are so many ways to define a function (sort of) in Julia! Some will blow your mind! Reading time: 5 min read

In the example a*b=a+b, do you want to say that 2*3 gives 5, not 6?

All ways to define functions in Julia?

General Usage

xiaodai June 2, 2021, 10:24am 40

this thread is getting better and better

Broadcast over struct fields?

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All ways to define functions in Julia?

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