When I define a wrong (or unuseful) type to a variable declaration I get an error as expected: my_var::Int64 = 3.2 However, when I continue to work in the REPL, it is impossible to re-define the variable: my_var = 3.2 It seems, that the variable type is stored in the REPL. How can I clear or red…

[image] joa-quim: Honestly, I find it incomprehensible that we can impose that a variable has to dress with a certain cloth to enter that box (the function) but once inside it can change clothes to what ever it wants. I look at it like this: The function signature foo(x::Int) is a filter on w…

[image] joa-quim: Honestly, I find it incomprehensible that we can impose that a variable has to dress with a certain cloth to enter that box (the function) but once inside it can change clothes to what ever it wants. Type-unstable variables are useful sometimes, and :: already means differen…

Just to clarify, my idea of a macro would be: macro looks at the signature of the function (that is all spelt out in code, no need to access any runtime information). macro changes the code of the function to add some lines in the following format at the start of the function body name_parameter_1…

Food for thought on that macro that enforces input type stability: julia> function foo(x::AbstractFloat) x::AbstractFloat = x x = 2 # convert(AbstractFloat, 2) x end; julia> typeof(1.5f0), typeof(foo(1.5f0)) (Float32, Float64) julia> function bar(x::AbstractFloat…

yeah that’s pretty easy to do: using ExprTools macro stable_argtypes(fdef) d = splitdef(fdef) args = get!(d, :args, []) arg_asserts = Expr(:block) foreach(args) do arg if Base.isexpr(arg, :(::), 2) name, type = arg.args push!(arg_asserts.args, :($nam…

EDIT: IGNORE THE ANSWER BELOW, I HAVE MISUNDERSTOOD WHAT THE MANUAL MEANT. This is kinda specific behaviour that comes from Base.convert : If T is a AbstractFloat type, then it will return the closest value to x representable by T. To be honest, I find quite unfortunate that convert (which is us…

Thank you very much! Unfortunately I have dabbled very little in actual macro writing and it would be hard for me to do it even if I see it is possible.

[image] Lukas_Hebing: It seems, that the variable type is stored in the REPL. How can I clear or redefine the type without restarting the kernel? As said before, you can’t undo global variables like that. Interestingly, the variable is still technically undefined because it’s not assigned, ev…

[image] Henrique_Becker: This shows that this trick can have cause the opposite of the desired effect, instead of helping the code to be type stable, it becomes type-unstable because the concrete type returned by convert(AbstractFloat, x) will depend on the value of x. No, convert(AbstractFlo…

[image] DNF: [image] joa-quim: Honestly, I find it incomprehensible that we can impose that a variable has to dress with a certain cloth to enter that box (the function) but once inside it can change clothes to what ever it wants. I look at it like this: The function signature foo(x::Int) …

How to re-define a variable completely?

New to Julia

de-souza June 15, 2023, 9:15am 36

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How to re-define a variable completely?

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