Iterator protocol for elements of Nemo.FinField

OrbitDecomposition.jl

@@ -11,20 +11,47 @@ import Nemo.elements
 
 using JLD
 
-function elements(F::Nemo.FqNmodFiniteField)
-    deg = Int(degree(F))
-    char = Int(characteristic(F))
-    z = (gen(F)^i for i in 0:deg-1)
-    crtsn_prd = Base.product([0:char-1 for i in 1:deg]...)
+include("Projections.jl")
 
-    function _it()
-        for crt in crtsn_prd
-            g = sum([b*a for (a,b) in zip(z,crt)])
-            produce(g)
+###############################################################################
+#
+#  Iterator protocol for Nemo.FinField
+#
+###############################################################################
+
+type FFEltsIter{T<:Nemo.FinField}
+    all::Int
+    field::T
+
+    function FFEltsIter(F::T)
+        return new(Int(characteristic(F)^degree(F)), F)
     end
-    end
-    return Task(_it)
 end
+FFEltsIter{T<:Nemo.FinField}(F::T) = FFEltsIter{T}(F)
+
+import Base: start, next, done, eltype, length
+
+Base.start(A::FFEltsIter) = (zero(A.field), 0)
+Base.next(A::FFEltsIter, state) = next_ffelem(state...)
+Base.done(A::FFEltsIter, state) = state[2] >= A.all
+Base.eltype(::Type{FFEltsIter}) = elem_type(A.field)
+Base.length(A::FFEltsIter) = A.all
+
+function next_ffelem(f::Nemo.FinFieldElem, c::Int)
+    if c == 0
+        return (f, (f, 1))
+    elseif c == 1
+        f = one(parent(f))
+        return (f, (f, 2))
+    else
+        f = gen(parent(f))*f
+        return (f, (f, c+1))
+    end
+end
+
+import Nemo.elements
+elements(F::Nemo.FinField) = FFEltsIter(F)
+
 
 function AutFG_emb(A::AutGroup, g::WreathProductElem)
     isa(A.objectGroup, FreeGroup) || throw("Not an Aut(Fₙ)")