How can I show all the methods of a function in Julia (multiple dispatch)?
For example, all the methods that exist in the namespace for the function abs.
How can I show all the methods of a function in Julia (multiple dispatch)?
For example, all the methods that exist in the namespace for the function abs.
The methods function will return the method table for the given function:
julia> methods(abs)
# 13 methods for generic function "abs":
[1] abs(a::Pkg.Resolve.FieldValue) in Pkg.Resolve at /home/david/pkg/julia-bin/julia-1.4.0-rc1/share/julia/stdlib/v1.4/Pkg/src/Resolve/fieldvalues.jl:61
[2] abs(a::Pkg.Resolve.VersionWeight) in Pkg.Resolve at /home/david/pkg/julia-bin/julia-1.4.0-rc1/share/julia/stdlib/v1.4/Pkg/src/Resolve/versionweights.jl:36
[3] abs(::Missing) in Base at missing.jl:100
[4] abs(x::Float64) in Base at float.jl:528
...
As of Julia 1.4, you can filter the method table by module. For example, listing the methods of abs which were defined in the Dates module:
julia> methods(abs, Dates)
# 1 method for generic function "abs":
[1] abs(a::T) where T<:Dates.Period in Dates at /home/david/pkg/julia-bin/julia-1.4.0-rc1/share/julia/stdlib/v1.4/Dates/src/periods.jl:95