gcalderone / AbbrvKW.jl

Allow using abbreviated keyword names in function calls

AbbrvKW

Use abbreviated keyword names in function calls.

Julia supports keyword arguments in function calls but the keyword names must be entirely specified, even when there is no possibility of ambiguity.

In order to improve code readability, and speed up interactive usage on the REPL, it may be useful to use abbreviated names in function calls while maintaining full descriptive names in the function definitions. This packages provide such functionality through the @AbbrvKW macro.

The idea for this macro came out from a post in the Usage forum. Hopefully, this functionality will be included as a native feature in future versions of Julia.

You may install this package typing:

Pkg.add("AbbrvKW")

in the Julia REPL.

Example

Consider the following function:

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

The only way to use the keywords is to type their entire names, resulting in very long code lines, i.e.:

Foo(Keyword1=10, AnotherKeyword=20.0, StillAnotherOne=30, KeyString="baz")

By processing the Foo function through the @AbbrvKW macro you may use abbreviated keywords, as long as the provided names allow complete disambiguation:

using AbbrvKW

@AbbrvKW function Foo(; Keyword1::Int=1, AnotherKeyword::Float64=2.0, StillAnotherOne=3, KeyString::String="bar")
    @show Keyword1
    @show AnotherKeyword
    @show StillAnotherOne
    @show KeyString
end
Foo(Keyw=10, A=20.0, S=30, KeyS="baz") # <-- Much shorter, isn't it?

The generated code also checks for unrecognized keyword, and raise an error in case they are found. If you wish to catch further keywords (and avoid raising an exception) simply add a symbol with a splat at the end of the keywords, e.g.:

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

Internals

To use the macro simply prepend @AbbrvKW to the function keyword. The macro will read the list of keywords and add code at the beginning of the function to handle keyword abbreviations. If the types are specified in the function definition the generated code will also typeassert the keywords.

The @macroexpand macro can be used to show the code generated by the @AbbrvKW macro, i.e.:

julia> @macroexpand @AbbrvKW function Foo(;Keyword::Float64=1., verboseLevel::Union{Void,Int}=nothing)
           println("Keyword: ", Keyword)
           if verboseLevel != nothing
               println("New verbosity level: ", verboseLevel)
           end
       end
	   
:(function Foo(; Keyword::Float64=1.0, verboseLevel::Union{Void, Int}=nothing, _abbrvkw_...)
        begin 
            _ii_ = 1
            while _ii_ <= length(_abbrvkw_)
                if (_abbrvkw_[_ii_])[1] in (:K, :Ke, :Key, :Keyw, :Keywo, :Keywor)
                    typeassert((_abbrvkw_[_ii_])[2], Float64)
                    Keyword = (_abbrvkw_[_ii_])[2]
                    deleteat!(_abbrvkw_, _ii_)
                    continue
                end
                if (_abbrvkw_[_ii_])[1] in (:v, :ve, :ver, :verb, :verbo, :verbos, :verbose, :verboseL, :verboseLe, :verboseLev, :verboseLeve)
                    typeassert((_abbrvkw_[_ii_])[2], Union{Void, Int})
                    verboseLevel = (_abbrvkw_[_ii_])[2]
                    deleteat!(_abbrvkw_, _ii_)
                    continue
                end
                _ii_ += 1
            end
            _ii_ = nothing
            if length(_abbrvkw_) != 0
                error("Unrecognized keyword abbreviation(s): " * string(_abbrvkw_))
            end
            _abbrvkw_ = nothing
        end
        println("Keyword: ", Keyword)
        if verboseLevel != nothing
            println("New verbosity level: ", verboseLevel)
        end
    end)