Ignore indentation effect of a specific block

[MilesCranmer]

Sometimes in my code I would like to use a macro on a block of code without indenting it. For example, I want to go from

const CONST = 1
function foo(x)
    x + CONST
end

to this:

@mymacro begin

const CONST = 1
function foo(x)
    x + CONST
end

end

This could be something like DispatchDoctor.jl @stable or Base.@assume_effects, which can operate on entire code blocks.

Now, if I have the formatter turned on, this will turn into

@mymacro begin

    const CONST = 1
    function foo(x)
        x + CONST
    end

end

This is of course valid, but I would like to disable it for the code block. I want the @mymacro begin to just sit at the top level without affecting the rest of the code. (It's kind of like how module A ... end doesn't indent everything in the contents.)

The only workaround at the moment is to use #! format: off for the entire code block. This works but it prevents me from using JuliaFormatter.jl for internal code.

Thus, @domluna, I was wondering if there could be a special command to ignore the increased indentation for a single block? Happy to help add it if you can point me to where to edit.

[MilesCranmer]

I should also mention I tried the first thing I thought of:

#! format: off
@mymacro begin
#! format: on

...

#! format: off
end
#! format: on

but this sadly did not work. (This might be the right API for this, because at the time it felt the most intuitive to me.)

[domluna]

I should also mention I tried the first thing I thought of:

#! format: off
@mymacro begin
#! format: on

...

#! format: off
end
#! format: on

but this sadly did not work. (This might be the right API for this, because at the time it felt the most intuitive to me.)

this should work, not sure why it doesn't.

essentially all this happens here:

https://github.com/domluna/JuliaFormatter.jl/blob/master/src/print.jl#L1-L79

[MilesCranmer]

Here's a MWE:

julia> using JuliaFormatter

julia> format_text("\n#! format: off\n@mymacro begin\n#! format: on\nfoo() = nothing\n#! format: off\nend\n#! format: on")
"\n#! format: off\n@mymacro begin\n#! format: on\n    foo() = nothing\n#! format: off\nend\n#! format: on"

You can see the extra spaces added before the foo()

(inline version of this:

#! format: off
@mymacro begin
#! format: on
foo() = nothing
#! format: off
end
#! format: on

[domluna]

unless I'm missing something this part

#! format: on
foo() = nothing
#! format: off

will be formatted and it is. Hmmm perhaps the confusion is the scope of the format on/off rule. It's based on the lines and that's it. so the initial format off in this case would just ignore doing anything to

@mymacro begin

[MilesCranmer]

Oh I think I got confused. So, in this case, how could I turn off indentation for a specific code block, without disabling formatting within said block?

[domluna]

indentation is tied to formatting so right now you can't

…

On Wed, Dec 11, 2024 at 9:29 PM Miles Cranmer ***@***.***> wrote: Oh I think I got confused. So, in this case, how could I turn off indentation for a specific code block, *without* disabling formatting within said block? — Reply to this email directly, view it on GitHub <#889 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAORUFZO7VFBDUIDAXUJWXT2FDYIZAVCNFSM6AAAAABTOSI7H6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDKMZXGYZTOOBVGA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[MilesCranmer]

I see, thanks. Could I request it as a new feature? I want to be able to remove a single indentation for a @mymacro begin block.

[domluna]

I'd be fine with it as a new feature but I probably won't get around to implementing this any time soon.

[MilesCranmer]

In case I or someone else reading this thread in the future wants to try adding it, where should we start?

[penelopeysm]

I think this works now:

julia> s = """
       @mymacro begin
       #! format: noindent
       const CONST = 1
       function foo(       x     )
           x + CONST
       end

       end

       @anothermacro begin
       42
       end"""
"@mymacro begin\n#! format: noindent\nconst CONST = 1\nfunction foo(       x     )\n    x + CONST\nend\n\nend\n\n@anothermacro begin\n42\nend"

julia> format_text(s) |> println
@mymacro begin
#! format: noindent
const CONST = 1
function foo(x)
    x + CONST
end

end

@anothermacro begin
    42
end

[penelopeysm]

(Specifically, it's the #! format: noindent in there: https://juliaeditorsupport.github.io/JuliaFormatter.jl/stable/skipping_formatting/#Preventing-indentation)