adding Base.getindex to Identity, analog to Base.get

Author: Stephan Sahm

src/Identity.jl

@@ -29,6 +29,8 @@ isidentity(other) = false
 Base.length(::Identity) = 1
 
 Base.get(a::Identity) = a.value
+Base.getindex(a::Identity) = a.value
+
 Base.eltype(::Type{<:Identity{T}}) where T = T
 Base.eltype(::Type{<:Identity}) = Any
 

test/Identity.jl

@@ -15,6 +15,7 @@ end == Identity(3 + 4)
 @test length(Identity([1,2,3,4])) == 1
 
 @test get(Identity(42)) == 42
+@test Identity(42)[] == 42
 
 @test isidentity(Identity(4))
 @test !isidentity(Const(3))