use .ext dictionary to store object dict

Author: hdavid16

README.md

@@ -35,7 +35,7 @@ When a disjunction is defined using the `@disjunction` macro, the disjunctions a
 
 For empty disjuncts, use `nothing` for their positional argument (e.g., `@disjunction(m, x <= 1, nothing, reformulation = :big_m)`).
 
-NOTE: `:gdp_variable_refs` are forbidden JuMP model object names when using *DisjunctiveProgramming.jl*. They are used to store the variable names and variable references in the original model.
+NOTE: `:object_dict` is used in the extension dictionary to store the object dictionary of models using *DisjunctiveProgramming.jl*.
 
 ## Logical Propositions
 

src/constraint.jl

@@ -44,7 +44,7 @@ function check_constraint!(m::Model, constr::ConstraintRef)
         constr_name = gen_constraint_name(constr)
         delete_constraint!(m, constr, constr_name)
         m[constr_name] = new_constr
-        m[:original_object_dict][constr_name] = new_constr
+        m.ext[:object_dict][constr_name] = new_constr
     end
     return new_constr
 end
@@ -67,7 +67,7 @@ function check_constraint!(m::Model, constr::AbstractArray{<:ConstraintRef})
         constr_name = gen_constraint_name(constr)
         delete_constraint!.(m, constr, constr_name)
         m[constr_name] = new_constr
-        m[:original_object_dict][constr_name] = new_constr
+        m.ext[:object_dict][constr_name] = new_constr
     end
     return new_constr
 end

src/reformulate.jl

@@ -8,12 +8,7 @@ Reformulate disjunction on a JuMP model.
 Reformulate disjunction.
 """
 function reformulate_disjunction(m::Model, disj...; bin_var, reformulation, param)
-    #get original variable refs and variable names
-    vars = setdiff(all_variables(m), m[bin_var])
-    if !in(:gdp_variable_refs, keys(object_dictionary(m)))
-        @expression(m, gdp_variable_refs, vars)
-    end
-    @expression(m, original_object_dict, object_dictionary(m))
+    m.ext[:object_dict] = copy(object_dictionary(m))
     #check disj
     disj = [check_constraint!(m, constr) for constr in disj]#check_disjunction!(m, disj)
     #run reformulation

src/utils.jl

@@ -71,15 +71,15 @@ function gen_constraint_name(constr::ConstraintRef)
     return Symbol(constr_name)
 end
 function gen_constraint_name(constr::NonlinearConstraintRef)
-    constr_name = findfirst(==(constr), constr.model[:original_object_dict])
+    constr_name = findfirst(==(constr), constr.model.ext[:object_dict])
     if isnothing(constr_name)
         constr_name = gensym("constraint")
     end
 
     return Symbol(constr_name)
 end
 function gen_constraint_name(constr::AbstractArray{<:NonlinearConstraintRef})
-    constr_name = findfirst(==(constr), first(constr).model[:original_object_dict])
+    constr_name = findfirst(==(constr), first(constr).model.ext[:object_dict])
     if isnothing(constr_name)
         constr_name = gensym("constraint")
     end