Whitespace sensitivity

Okay, good to know then, because I don’t think anybody does this weird space thing. I was just saying the only reason I’d think of is if that’s for Lisp, i.e. postfix

Matlab, Python, C, Fortran, Java, Swedish, English and German - these are the languages I’m on first name basis with, and I’ve never seen or written f ( x ) in any of them. It would probably confuse me if I saw it, and disallowing it is at worst harmless and more likely a good thing for legibility.


In principle I agree with you but this particular restriction I really don’t have a problem with.

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I’ve seen something like this once: In C# scripts used by the Unity game engine. I don’t know why.

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Having the right to use whitespace at your own disposal is one thing and actually using it is another thing. Nothing stops you from using whitespace in these languages if it helps improve readability, and I encountered many examples in C (see Linux Kernel) and Fortran doing this. Writing f(x) in English is wrong, by the way. Check also languages like Haskell, OCaml, F#, Lisp, Closure, Forth, Elm, Standard ML, Ada, V, …etc., they do this all the time. And languages that use {..} always add space around and inside the braces; check Rust, C/C++, LaTeX, …etc. I mean, restricting something requires a strong reason because it feels bad to be punished just for adding a space after the function name. Of course f ( x ) seems ugly because the function name and arguments are short, but it feels a bit weird to disallow it.

People often have very strong opinions about surface syntax like this, but in the end it just comes down to personal preference, there is really no objectively superior choice. In past experience, this tends to lead to long circular discussions with little productive outcome. Julia’s syntax is finalized at this point – Except for new non-breaking features and minor consistency improvements the syntax just won’t change. I know it’s a bit of a cliché, but I think at this point, we will just have to agree to disagree. :wink:


f(x) is not wrong in English because of the whitespace. It’s wrong in English because natural languages don’t have function calls.

LaTeX is another example where I have a lot of familiarity and you’re just wrong there. People do not leave a space between the macro name and the argument brackets “all the time”. If you write \macro {something} in LaTeX anyone who reads your code will assume that macro is a zero argument macro. It’s valid code, but it’s rare and bad.


I find it’s just habit. After using one language continuously for a while, I tend to acquire the quirks of that language and when I switch to another language I tend to dislike the new quirks, but after a few months I adapt and change… conventions about underscores, capital letters, space inside arguments vs space inside expressions, omitting or reinserting curly brackets, etc. I have hated and liked them in equal measure. I guess I don’t have the personality to have a personal preference!

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Doesn’t prohibiting such white spaces in functional notation bring Julia closer to Prof. Edelman’s motto: “with Julia, you don’t code the math, code is the math”?

See his TEDx talk.

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I’m not complaining about syntax, and I know that Julia’s syntax is finalized. I’m talking about a restriction that can be another source of error in the code if one innocently added one space after the function name. I don’t like that space either, but disallowing it was a bit extreme and sounds to me like a step back in programming language design (Fortran adopted free form after Fortran 77). Syntax in not a problem because one adapts to it after some time as @ptoche said, but this is about a strange behavior not found in other languages and can introduce errors.

That’s true, but look at the new LaTeX3 Layer and you’ll see a lot of spaces around and inside { }s for clarity of arguments.

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Yes, of course, if what you write is math, then f(x) should exactly be written like that. But Julia is also a general purpose programming language and one can encouter pretty long function names like below. Introducing one space sometimes doesn’t hurt.


function get_substitutions_and_solved_states(sys; no_postprocess=false)

sin (π/6)^2 === horrendous

Yes, horrendous, because it is far from math. This is exactly what I said above.

they still call functions without space no?

what does this even mean? everything is still function, math functions have short name because people can’t write verbosely on blackboard so they overload symbols all the time, do you prefer Unicode programming maybe? In any language you can have verbose (english, you may say) function names:

still, people don’t do it. It’s fine you have personal preference, just know it’s rarely adopted and Julia is NOT going to change its syntax, not sure if there’s anything to this discussion anymore



It’s not required by any means, but it’s not disallowed by C# and somehow Unity adopted it as a convention in places. I could see a “readability” argument for the preference.

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I wonder if that webpage (not focused on coding style anyway) was made by someone not paying attention to coding style:

it’s funny they don’t even explicitly say “no space” for function call…

C also allows it, these language tends to “allow” simply because they don’t have a lot of syntax sugar and is filled with {} and ; so they are minimally sensitive to spacing of any kind, including linebreak

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That seems to be some random person who made a style guide?

In any case, they may have been changing to standard C# style. When I first used Unity years ago, it was spaces everywhere.


I see, in that case I will remember Unity as the first large community I know of that commonly uses func (x) style

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