Allow priorities to be Floats

Extended the store and container objects so that priorities are not restricted to being integers.
This is a more general expression of priority which may make it easier at some point to use rank functions (JuliaDynamics#75).
This also avoids having to normalize (and sometimes scaling) priorities so that they are integer in queueing systems.

src/resources/containers.jl

@@ -1,5 +1,5 @@
 struct ContainerKey{N<:Real} <: ResourceKey
-  priority :: Int
+  priority :: Real
   id :: UInt
   amount :: N
 end
@@ -22,25 +22,25 @@ end
 
 const Resource = Container{Int}
 
-function put(con::Container{N}, amount::N; priority::Int=0) where N<:Real
+function put(con::Container{N}, amount::N; priority::Real=0) where N<:Real
   put_ev = Put(con.env)
   con.put_queue[put_ev] = ContainerKey(priority, con.seid+=one(UInt), amount)
   @callback trigger_get(put_ev, con)
   trigger_put(put_ev, con)
   put_ev
 end
 
-request(res::Resource; priority::Int=0) = put(res, 1; priority=priority)
+request(res::Resource; priority::Real=0) = put(res, 1; priority=priority)
 
-function get(con::Container{N}, amount::N; priority::Int=0) where N<:Real
+function get(con::Container{N}, amount::N; priority::Real=0) where N<:Real
   get_ev = Get(con.env)
   con.get_queue[get_ev] = ContainerKey(priority, con.seid+=one(UInt), amount)
   @callback trigger_put(get_ev, con)
   trigger_get(get_ev, con)
   get_ev
 end
 
-release(res::Resource; priority::Int=0) = get(res, 1; priority=priority)
+release(res::Resource; priority::Real=0) = get(res, 1; priority=priority)
 
 function do_put(con::Container{N}, put_ev::Put, key::ContainerKey{N}) where N<:Real
   con.level + key.amount > con.capacity && return false

src/resources/stores.jl

@@ -1,12 +1,12 @@
 struct StorePutKey{T} <: ResourceKey
-  priority :: Int
+  priority :: Real
   id :: UInt
   item :: T
   StorePutKey{T}(priority, id, item) where T = new(priority, id, item)
 end
 
 struct StoreGetKey <: ResourceKey
-  priority :: Int
+  priority :: Real
   id :: UInt
   filter :: Function
 end
@@ -24,7 +24,7 @@ mutable struct Store{T} <: AbstractResource
   end
 end
 
-function put(sto::Store{T}, item::T; priority::Int=0) where T
+function put(sto::Store{T}, item::T; priority::Real=0) where T
   put_ev = Put(sto.env)
   sto.put_queue[put_ev] = StorePutKey{T}(priority, sto.seid+=one(UInt), item)
   @callback trigger_get(put_ev, sto)
@@ -34,7 +34,7 @@ end
 
 get_any_item(::T) where T = true
 
-function get(sto::Store{T}, filter::Function=get_any_item; priority::Int=0) where T
+function get(sto::Store{T}, filter::Function=get_any_item; priority::Real=0) where T
   get_ev = Get(sto.env)
   sto.get_queue[get_ev] = StoreGetKey(priority, sto.seid+=one(UInt), filter)
   @callback trigger_put(get_ev, sto)