Hi! I am trying to extend the methods of a collection of functions programmatically with no partial success. foo(x::Real) = x for f in (:foo,) @eval ($f)(x::Complex) = x' end function fun() foo(x::Real) = x for f in (:foo,) @eval ($f)(x::Complex) = x' end return foo end…

I have updated the script with something more eloquent. foo(x::Real) = x f = :foo eval("$f(x::Complex) = x'") display(foo) display(eval(f)) function fun() goo(x::Real) = x g = :goo eval("$g(x::Complex) = x'") display(goo) display(eval(g)) return goo end bar = fun() foo (ge…

[image] vitaminace33: function fun() goo(x::Real) = x g = :goo eval("$g(x::Complex) = x'") display(goo) display(eval(g)) return goo end You’re returning a local variable goo. It’s not associated with the global symbol :goo. However, eval always runs in global scope and…

You’re returning a local variable goo. Yes indeed It’s not associated with the global symbol :goo. Why do you say “global”? There is no global symbol :goo. However, eval always runs in global scope and creates the only function associated with the global symbol :goo. Had the first eval ru…

I think you’re dealing with a “world age” issue. [image] World Age Problem Explanation General Usage Hello. Recently I have faced the “world age problem” several times. That means, after searching for my problems, this website came up with themes like “world age workarou…

[image] vitaminace33: Had the first eval run in global scope, a function called goo in global scope should be defined for complex numbers Every eval runs in global scope, and eval’ing a string does not define a function, it merely evals the string. Your first example, with the foo functions s…

[image] sgaure: eval’ing a string does not define a function, it merely evals the string. Right! I was on my phone and didn’t notice that earlier. Eval operates on expressions. You’d need to parse it first!

[image] sgaure: eval’ing a string does not define a function, it merely evals the string I did not know/understand this, thx. [image] sgaure: A slight variation shows what happens: It is similar to my second example but more clarifying, thx again. Coming back to my initial post, how …

I’m not sure if you are mixing different concepts here. The following seems to work for me fun_returning() = x::Real -> x proc_evaluating() = @eval foo(x::Complex) = x bar = fun_returning() @show bar(42.0) proc_evaluating() @show foo(Complex(42.0, 43.0)) yielding bar(42.0) = 42.0 foo(Complex(42.0…

Thx but this is not what I need. [image] vitaminace33: I would like bar to have two methods, the ones that currently have foo and bar itself. Documentation refers to this and it seems to be world age realated.

OK, let us try test() = begin @eval foo(x::Real) = x @eval foo(x::Complex) = x end test() varinfo() yielding name size summary –––––––––––––––– ––––––––––– ––––––––––––––––––––––––––––––––––––– Base Module Core Mod…

Using @eval in a function

General Usage

dlakelan October 29, 2022, 3:45pm 5

I think you’re dealing with a “world age” issue.

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Using @eval in a function

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