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…

struct Name <: Function end (::Name)(a,b) = a+b const name = Name()

[image] jzr: “functors” and everywhere else yeah, i got a pure math degree so functor is a totally different thing to me I think.

[image] xiaodai: if false name = (a,b) -> a+b end What do you mean by that example? If you enter it at the Julia prompt, then name is not defined afterwards.

What about this one? function fn_generator() if true f() = 0 else f(x, y) = x+y end end name = fn_generator() name(1,2) # 3

This is the same as function fn_generator() f(x, y) = x+y end since true branch is ignored. And original version should produce warning in 1.6 or 1.7

This is surprising. What is happening here?

The last definition of f is used. Some may see this as a bug. To avoid this “behaviour” use anonymous functions instead. julia> function fn_generator() if true f = () -> 0 else f = (x, y) -> x+y end end fn_generator (generic func…

[image] Skoffer: And original version should produce warning in 1.6 or 1.7 I don’t see a warning for either version. Can you demonstrate this? UPDATE: Ah, I see, the function signature must be the same (it isn’t in the example above): julia> function fn_generator() if true …

All ways to define functions in Julia?

General Usage

xiaodai May 29, 2021, 2:47am 16

cool

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All ways to define functions in Julia?

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