restrict the domain field

ChrisRackauckas · ChrisRackauckas · commit 218f07ac06a4 · 2018-03-18T14:03:09.000-07:00
diff --git a/src/variables.jl b/src/variables.jl
@@ -8,7 +8,7 @@ struct Variable <: Expression
     dependents::Vector{Variable}
     description::String
     flow::Bool
-    domain
+    domain::AbstractDomain
     size
     context
 end
