WhereTraits.BasicTraits
For anology with SimpleTraits.jl, this package comes with standard traits definitions ismutable, isimmutable, isiterable, iscallable, isbitstype, isconcretetype. They mostly just wrap respective standard definitions in Base, with the added benefit, that they behave similarly to Base.eltype in that they have the convenience fallback ismutable(value) = ismutable(typeof(value)).
You can use them by executing the following
using WhereTraits
using WhereTraits.BasicTraits
WhereTraits.BasicTraits.@overwrite_Base
ismutable(1) # false
ismutable("string") # true
ismutable(String) # truePlease consult the file test/BasicTraits.jl for more examples.