Hi all, I suddenly had a “metaphysical” doubt when learning about the @static macro. I imagined that such macro could be used to completly evaluate a given expression and replace it by its result at compile time. It cannot. Then I though that maybe @eval would do that. But trying julia> a=1 juli…

But what if function f instead of returning a global variable, makes a check of the system by running some program, which one intends to be ran only once at compile time?

What do you mean by “compile time”. If it’s just a cache, then do just that. You can even write a macro to do it. If it depends on input types and by compile time you mean inference time, then it can be valid to use generated function in some cases as long as you are not calling any functions define…

I mean something like “parsing time” or “precompilation time”. I mean something that does not depends on future inferences of g() function due to it being called with new argument types. But I guess I found the way this is usually done, it uses your first answer indeed but applied to the definition…

Sure, I stand corrected. (I initially tried doing g() = @eval $(f()) that’s why it didn’t work.)

Evaluate and capture expression result into function/closure body

General Usage

yuyichao June 7, 2017, 11:43pm 2

You can splice in a value directly

@eval f() = $a

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Evaluate and capture expression result into function/closure body

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