#29 - out_transitions for location with no transitions

[schillic]

This is one attempt to close #29. This workaround is not very elegant due to the restriction that I want to make the code type stable. Note that it relies on LightGraphs to return an empty list for non-existing nodes. I understand if you do not accept this workaround.

[codecov[bot]]

Codecov Report

Merging #30 into master will decrease coverage by 1.84%. The diff coverage is 50%.

@@            Coverage Diff             @@
##           master      #30      +/-   ##
==========================================
- Coverage   81.36%   79.51%   -1.85%     
==========================================
  Files           6        6              
  Lines         161      166       +5     
==========================================
+ Hits          131      132       +1     
- Misses         30       34       +4

Impacted Files	Coverage Δ
src/light.jl	74.66% <50%> (-3.91%)	:arrow_down:

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[schillic]

Sorry, I do not see how to incorporate the type in the proper way :disappointed:

[mforets]

How about:

$ git diff
diff --git a/src/light.jl b/src/light.jl
index 42859d3..b729e37 100644
--- a/src/light.jl
+++ b/src/light.jl
@@ -171,7 +171,7 @@ function in_transitions(A::LightAutomaton, s)
     LightTransitionIterator(A, edges)

 end
 function out_transitions(A::LightAutomaton, s)
-    edges = MappedArrays.mappedarray(dst -> edge_object(A, s, dst),
+    edges = MappedArrays.mappedarray(Int, dst -> edge_object(A, s, dst),
                                      LightGraphs.outneighbors(A.G, s))
     LightTransitionIterator(A, edges)
 end

Then:

julia> out_transitions(H, 2)
LightTransitionIterator{SimpleDiGraph{Int64},LightGraphs.SimpleGraphs.SimpleEdge{Int64},MappedArrays.MultiMappedArray{Int64,1,Tuple{Arra
y{Int64,1}},Type{Int64},getfield(Main, Symbol("##5#6")){LightAutomaton{SimpleDiGraph{Int64},LightGraphs.SimpleGraphs.SimpleEdge{Int64}},
Int64}}}(LightAutomaton{SimpleDiGraph{Int64},LightGraphs.SimpleGraphs.SimpleEdge{Int64}}({2, 2} directed simple Int64 graph, Dict(Edge 1
 => 1=>Dict(1=>1),Edge 1 => 2=>Dict(2=>2)), 2, 2), Int64[])

julia> isempty(out_transitions(H, s))
true

Sorry, I do not see how to incorporate the type in the proper way

The types of source and dest are always Int's (see this line).

[schillic]

I also tried that, but the result differs from the previous one in master (ReadonlyMappedArray vs. MultiMappedArray). See this example with a println(out_transitions(H, 1)). in master:

HybridSystems.LightTransitionIterator{
    LightGraphs.SimpleGraphs.SimpleDiGraph{Int64},
    LightGraphs.SimpleGraphs.SimpleEdge{Int64},
    MappedArrays.ReadonlyMappedArray{
        LightGraphs.SimpleGraphs.SimpleEdge{Int64},1,Array{Int64,1},
        getfield(HybridSystems, Symbol("##21#22")){LightAutomaton{
            LightGraphs.SimpleGraphs.SimpleDiGraph{Int64},
            LightGraphs.SimpleGraphs.SimpleEdge{Int64}},Int64}
    }
}(LightAutomaton{LightGraphs.SimpleGraphs.SimpleDiGraph{Int64},
                 LightGraphs.SimpleGraphs.SimpleEdge{Int64}}
    ({2, 2} directed simple Int64 graph,
     Dict(Edge 1 => 2=>Dict(2=>2),Edge 1 => 1=>Dict(1=>1)), 2, 2),
  LightGraphs.SimpleGraphs.SimpleEdge{Int64}[Edge 1 => 1, Edge 1 => 2])

using Int:

HybridSystems.LightTransitionIterator{
    LightGraphs.SimpleGraphs.SimpleDiGraph{Int64},
    LightGraphs.SimpleGraphs.SimpleEdge{Int64},
    MappedArrays.MultiMappedArray{
        Int64,1,Tuple{Array{Int64,1}},Type{Int64},
        getfield(HybridSystems, Symbol("##25#26")){
            LightAutomaton{LightGraphs.SimpleGraphs.SimpleDiGraph{Int64},
            LightGraphs.SimpleGraphs.SimpleEdge{Int64}},Int64}
    }
}(LightAutomaton{LightGraphs.SimpleGraphs.SimpleDiGraph{Int64},
                 LightGraphs.SimpleGraphs.SimpleEdge{Int64}}
    ({2, 2} directed simple Int64 graph,
     Dict(Edge 1 => 2=>Dict(2=>2),Edge 1 => 1=>Dict(1=>1)), 2, 2), [1, 2])

[schillic]

The types of source and dest are always Int's (see this line).

True, but the expected type for MappedArrays is the result type of the mapping, which should be the "edge type". See here: T is the type after applying the function.