Remove SubmittedIndex

Author: blegat

src/attributes.jl

@@ -377,7 +377,7 @@ end
 
 """
     submit(optimizer::AbstractOptimizer, sub::AbstractSubmittable,
-           value)::Union{Nothing, SubmittedIndex{typeof(sub)}}
+           value)::Nothing
 
 Submit `value` to the submittable `sub` of the optimizer `optimizer`.
 

src/indextypes.jl

@@ -35,21 +35,10 @@ end
 # https://github.com/JuliaLang/julia/issues/10208
 Base.hash(v::VariableIndex, h::UInt) = hash(v.value, h)
 
-"""
-    SubmittedIndex{SubmitType}
-
-A type-safe wrapper for `Int64` for use in referencing elements submitted for
-submittable of type `SubmitType`.
-"""
-struct SubmittedIndex{SubmitType}
-    attr::SubmitType
-    value::Int64
-end
-
 # No need to define isequal because the default matches our implementation of
 # hash.
 
-const Index = Union{ConstraintIndex, VariableIndex, SubmittedIndex}
+const Index = Union{ConstraintIndex,VariableIndex}
 
 """
     struct InvalidIndex{IndexType<:Index} <: Exception