Keyword name disambiguation

General Usage
1

I’ working on a code which, for the sake of clarity, has long keyword names.
A simple example is:

function foo(;ABooleanKeyword=false, AnotherLooongKeyword=2)
    println(ABooleanKeyword)
    println(AnotherLooongKeyword)
end

Is there a simply way to call the foo function with abbreviated keyword names, such as foo(ABoo=true, Another=4) ?
There would be no ambiguity in this case…

Also, since the default value of the first keyword is a boolean, it would be nice and clear (IMHO) if I could use it as an on/off switch being on when the keyword is provided, off otherwise, i.e.

foo(ABoo)  ==> ON
foo()  ==> OFF

In the first case there would be an ambiguity on whether ABoo is the keyword or another symbol. However, a syntax similar to foo(/ABoo), foo(>ABoo), foo(;ABoo) etc… would remove any ambiguity.

Is there a simple way to do this already implemented in Julia ?

2

This mechanism reminds me of R, but AFAICT Julia has nothing similar, and implementing this would require complex macrology/introspection.

In Julia, it is common practice to wrap up bundles of repeated keyword parameters in a structure.

3

I believe Plots.jl does allow for various keyword argument aliases, but I’m unsure
how it does this.

Cheers,
Kevin

4

Isn’t that for when you have many parameters? The problem here is the length of the names.

1 Like
5

I created a small macro to fulfill my purpose. It is available as a package here:
https://github.com/gcalderone/AbbrvKW.jl

To use it go from:

function Foo(; Keyword1::Int=1, AnotherKeyword::Float64=2.0, StillAnotherOne=3, KeyString::String="bar")
...
end

to:

using AbbrvKW

function Foo(; kw...)
    @AbbrvKW(kw, Keyword1::Int=1, AnotherKeyword::Float64=2.0, StillAnotherOne=3, KeyString::String="bar")
   ...
end

This way I can call the Foo function with abbreviated keyword names, as long as the provided names allow complete disambiguation, i.e.:

Foo(Keyw=10, A=20.0, S=30, KeyS="baz")

I would like to see this functionality included as a native feature in future versions of Julia, but I have no idea on how to implement it, nor how much effort it requires… :frowning:

Comments/suggestions are welcome!

6

Lots of dictionaries: https://github.com/JuliaPlots/Plots.jl/blob/master/src/args.jl . ODEInterfaceDiffEq.jl does it similarly in order to translate DiffEq commands to ODEInterface.jl: https://github.com/JuliaDiffEq/ODEInterfaceDiffEq.jl/blob/master/src/solve.jl#L138

This idea works well en masse, but if just handling a few args it would be tedious at best.

1 Like