I’m new to Julia, but not to programming, so to help me learn, I’m writing some notes and training material. While reading Python Crash Course, the author describes a variable as: Variables are often described as boxes you can store values in. This idea can be helpful the first few times you use …

Yeah, I also like the label analogy. I think it helps clarify that y = x doesn’t do anything other than associate the name :y with the current value of x. The good news is that if you’re used to Python’s variable semantics, you should find that Julia’s behavior generally matches your expectations. …

You can think of variables as living inside boxes, the box being the module scope. For example, if you assign a new variable in module module MyModule var = "var label" end Then this var is boxed into the MyModule scope, so you must access it as MyModule.var unless you export or import it into an…

Ok, I arrived late, but let me do one more analogy: Forget boxes. Boxes do not exist. Period. When you create an object it simply exists. Semantically does not matter where it lives. (For performance reason it may matter but this is another topic.) If you just create an object inside an expressio…

[image] Henrique_Becker: structs are just a pile of labels As a new Julia user, I still see a lot of haze around its memory model. I wish there was a more formal description somewhere, which didn’t rely on other languages’ memory model as Functions · The Julia Language does. Coming from C++ b…

[image] pauljurczak: I wish there was a more formal description somewhere, You can find this in the developer documentation section of the manual, for users who really need an answer. https://docs.julialang.org/en/v1/devdocs/object/ The layout of the object depends on its type. I do agre…

[image] pauljurczak: As a new Julia user, I still see a lot of haze around its memory model. I wish there was a more formal description somewhere, which didn’t rely on other languages’ memory model For what reason do you want to know more. Just for the sake of knowing or is there any actual c…

[image] pauljurczak: As a new Julia user, I still see a lot of haze around its memory model. I wish there was a more formal description As a user, arguably you almost never really have a need to know, unless you are interfacing with C. Abstractions are a programmer’s best friend. Also, unders…

[image] kristoffer.carlsson: For what reason do you want to know more. Just for the sake of knowing or is there any actual code that you write that depends on knowin I was making a lot of basic mistakes in the first few weeks, trying to stretch C/C++ memory model to understand what is going o…

[image] Tamas_Papp: Abstractions are a programmer’s best friend And abstraction is what I’m looking for, not a byte layout, although I needed that too for C interface. I would like something a bit more formal than structs are just a pile of labels.

[image] pauljurczak: I was making a lot of basic mistakes in the first few weeks, trying to stretch C/C++ memory model to understand what is going on. By memory model , I don’t mean implementation details. I’m looking for something less fuzzy than label and box , whatever that means. Okay, so…

Here is an example I just run into, which I can’t parse using a = expression makes a evaluate to the object expression is evaluated to within the scope a is valid rule. I’m expecting a behavior similar to: a = b = 42 where a and b evaluate to the same value, but in this code snippet: using…

Is it appropriate to say a variable is a label or box?

New to Julia

pauljurczak September 19, 2020, 6:03am 34

Sorry for a delay, but this is another puzzle I don’t understand given vague definitions of fundamental concepts: I thought I understood "pass-by-sharing" in Julia until I found this

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Is it appropriate to say a variable is a label or box?

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