I have a scenario where I think it might be warranted to depart from the end with an exclamation mark convention for function names that modify at least one of their arguments. However, I wouldn’t want to get into an anti-pattern here - so I am really curious about your take on this. I think the b…

The ! is just a convention, designed to be a helpful signal to end users about what the function may or may not do. IMO it all depends on the use-case and how you might imagine callers reasoning about the function call.

[image] algunion: Or, is myfun a legitimate option? IMO it isn’t. There are many functions with a bang that might fail to modify their argument for some reason. The bang is here to tell you that they might. julia> push!(Int[], 0.5) ERROR: InexactError: Int64(0.5) Stacktrace: [1] Int64 @ …

Just to be sure about your intended message: do you mean I should switch to myfun! and drop the myfun (given the function might modify the argument)? I am writing this because you quoted should I switch to myfun! in this scenario? but you replied you shouldn’t. However - the rest of your message se…

This is a mutating function, and should end with a ! There are some exceptions, like print, which don’t end with a !, but I don’t see that this is a relevant comparison. Keep the !

I was trying to confuse you. And me. Mission accomplished :sunglasses: Also, just edited my message

Another convention that I think is nice is the !! convention from BangBang.jl , where push!!(v, x) is something like if x fits_in v push!(v, x) else vcat(v, [x]) end i.e. the function is allowed to choose if it does mutation or an out-of-place operation. The mutation is basically an optimiz…

Thanks - after reading your messages, I will opt for bang usage in my scenario. To not open a new topic - and somewhat derived from the present one - how about the callable objects? Continuing the MWE from OP: function (x::MyStruct)(someargs...) y = 1 # resulted from the logic success = t…

A mutable callable object is kinda cursed :rofl: I guess you have no other choice than to document it thoroughly

I guess in this case one could just advise that people name the callable object with a !. i.e. function (x!::MyStruct)(someargs...) y = 1 # resulted from the logic success = true # can also be false - depending on the logic success && x!.updatable && push!(x!.arr, y) return x! e…

What if your mutatable callable object computed factorials?

Breaking notation convention - a potential anti-pattern?

General Usage

gdalle July 18, 2023, 5:25am 15

Actually, my “don’t” was a response to this, as in “don’t even go there it is beyond cursed”

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Breaking notation convention - a potential anti-pattern?

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