more iterator trait declarations

make HasEltype and HasLength the default

Author: JeffBezanson

base/channels.jl

@@ -95,3 +95,5 @@ function done(c::Channel, state::Ref)
     end
 end
 next{T}(c::Channel{T}, state) = (v=get(state[]); state[]=nothing; (v, state))
+
+iteratorsize{C<:Channel}(::Type{C}) = SizeUnknown()

base/dict.jl

@@ -4,9 +4,6 @@
 
 abstract Associative{K,V}
 
-iteratorsize{T<:Associative}(::Type{T}) = HasLength()
-iteratoreltype{T<:Associative}(::Type{T}) = HasEltype()
-
 const secret_table_token = :__c782dbf1cf4d6a2e5e3865d7e95634f2e09b5902__
 
 haskey(d::Associative, k) = in(k,keys(d))

base/generator.jl

@@ -26,9 +26,10 @@ abstract IteratorSize
 immutable SizeUnknown <: IteratorSize end
 immutable HasLength <: IteratorSize end
 immutable HasShape <: IteratorSize end
+immutable IsInfinite <: IteratorSize end
 
 iteratorsize(x) = iteratorsize(typeof(x))
-iteratorsize(::Type) = SizeUnknown()
+iteratorsize(::Type) = HasLength()  # HasLength is the default
 
 and_iteratorsize{T}(isz::T, ::T) = isz
 and_iteratorsize(::HasLength, ::HasShape) = HasLength()
@@ -40,19 +41,16 @@ immutable EltypeUnknown <: IteratorEltype end
 immutable HasEltype <: IteratorEltype end
 
 iteratoreltype(x) = iteratoreltype(typeof(x))
-iteratoreltype(::Type) = EltypeUnknown()
+iteratoreltype(::Type) = HasEltype()  # HasEltype is the default
 
 and_iteratoreltype{T}(iel::T, ::T) = iel
 and_iteratoreltype(a, b) = EltypeUnknown()
 
 iteratorsize{T<:AbstractArray}(::Type{T}) = HasShape()
-iteratorsize{T<:AbstractString}(::Type{T}) = HasLength()
-iteratorsize{T<:Tuple}(::Type{T}) = HasLength()
 iteratorsize{I,F}(::Type{Generator{I,F}}) = iteratorsize(I)
 length(g::Generator) = length(g.iter)
 size(g::Generator) = size(g.iter)
 
-iteratoreltype{T<:AbstractArray}(::Type{T}) = HasEltype()
-iteratoreltype{T<:AbstractString}(::Type{T}) = HasEltype()
+iteratoreltype{I,T}(::Type{Generator{I,T}}) = EltypeUnknown()
 iteratoreltype{I,T}(::Type{Generator{I,Type{T}}}) = HasEltype()
 eltype{I,T}(::Type{Generator{I,Type{T}}}) = T

base/io.jl

@@ -378,6 +378,8 @@ eltype(::Type{EachLine}) = ByteString
 
 readlines(s=STDIN) = collect(eachline(s))
 
+iteratorsize(::Type{EachLine}) = SizeUnknown()
+
 # IOStream Marking
 # Note that these functions expect that io.mark exists for
 # the concrete IO type. This may not be true for IO types

base/iterator.jl

@@ -125,6 +125,7 @@ done(f::Filter, s) = s[1]
 
 eltype{I}(::Type{Filter{I}}) = eltype(I)
 iteratoreltype{F,I}(::Type{Filter{F,I}}) = iteratoreltype(I)
+iteratorsize{T<:Filter}(::Type{T}) = SizeUnknown()
 
 # Rest -- iterate starting at the given state
 
@@ -140,6 +141,7 @@ done(i::Rest, st) = done(i.itr, st)
 
 eltype{I}(::Type{Rest{I}}) = eltype(I)
 iteratoreltype{I,S}(::Type{Rest{I,S}}) = iteratoreltype(I)
+iteratorsize{T<:Rest}(::Type{T}) = SizeUnknown()
 
 # Count -- infinite counting
 
@@ -152,12 +154,13 @@ countfrom(start::Number)               = Count(start, one(start))
 countfrom()                            = Count(1, 1)
 
 eltype{S}(::Type{Count{S}}) = S
-iteratoreltype{I<:Count}(::Type{I}) = HasEltype()
 
 start(it::Count) = it.start
 next(it::Count, state) = (state, state + it.step)
 done(it::Count, state) = false
 
+iteratorsize{S}(::Type{Count{S}}) = IsInfinite()
+
 # Take -- iterate through the first n elements
 
 immutable Take{I}
@@ -168,6 +171,7 @@ take(xs, n::Int) = Take(xs, n)
 
 eltype{I}(::Type{Take{I}}) = eltype(I)
 iteratoreltype{I}(::Type{Take{I}}) = iteratoreltype(I)
+iteratorsize{T<:Take}(::Type{T}) = SizeUnknown()  # TODO
 
 start(it::Take) = (it.n, start(it.xs))
 
@@ -192,6 +196,7 @@ drop(xs, n::Int) = Drop(xs, n)
 
 eltype{I}(::Type{Drop{I}}) = eltype(I)
 iteratoreltype{I}(::Type{Drop{I}}) = iteratoreltype(I)
+iteratorsize{T<:Drop}(::Type{T}) = SizeUnknown()  # TODO
 
 function start(it::Drop)
     xs_state = start(it.xs)
@@ -217,6 +222,7 @@ cycle(xs) = Cycle(xs)
 
 eltype{I}(::Type{Cycle{I}}) = eltype(I)
 iteratoreltype{I}(::Type{Cycle{I}}) = iteratoreltype(I)
+iteratorsize{I}(::Type{Cycle{I}}) = IsInfinite()
 
 function start(it::Cycle)
     s = start(it.xs)
@@ -241,7 +247,7 @@ immutable Repeated{O}
 end
 repeated(x) = Repeated(x)
 eltype{O}(::Type{Repeated{O}}) = O
-iteratoreltype{O}(::Type{Repeated{O}}) = HasEltype()
+iteratorsize{O}(::Type{Repeated{O}}) = IsInfinite()
 start(it::Repeated) = nothing
 next(it::Repeated, state) = (it.x, nothing)
 done(it::Repeated, state) = false

base/libgit2/reference.jl

@@ -181,6 +181,8 @@ function Base.next(bi::GitBranchIter, state)
     return (state[1:2], (GitReference(ref_ptr_ptr[]), btype[1], false))
 end
 
+Base.iteratorsize(::Type{GitBranchIter}) = Base.SizeUnknown()
+
 function Base.map(f::Function, bi::GitBranchIter)
     res = nothing
     s = start(bi)

base/libgit2/walker.jl

@@ -25,6 +25,8 @@ function Base.next(w::GitRevWalker, state)
     return (state[1], (id_ptr[], false))
 end
 
+Base.iteratorsize(::Type{GitRevWalker}) = Base.SizeUnknown()
+
 function push_head!(w::GitRevWalker)
     @check ccall((:git_revwalk_push_head, :libgit2), Cint, (Ptr{Void},), w.ptr)
     return w

base/multidimensional.jl

@@ -3,7 +3,7 @@
 ### Multidimensional iterators
 module IteratorsMD
 
-import Base: eltype, length, start, done, next, last, getindex, setindex!, linearindexing, min, max, eachindex, ndims
+import Base: eltype, length, size, start, done, next, last, getindex, setindex!, linearindexing, min, max, eachindex, ndims, iteratorsize
 importall ..Base.Operators
 import Base: simd_outer_range, simd_inner_length, simd_index, @generated
 import Base: @nref, @ncall, @nif, @nexprs, LinearFast, LinearSlow, to_index, AbstractCartesianIndex
@@ -103,6 +103,7 @@ end
 end
 
 eltype{I}(::Type{CartesianRange{I}}) = I
+iteratorsize{I}(::Type{CartesianRange{I}}) = Base.HasShape()
 
 @generated function start{I<:CartesianIndex}(iter::CartesianRange{I})
     N = length(I)
@@ -135,13 +136,15 @@ start{I<:CartesianIndex{0}}(iter::CartesianRange{I}) = false
 next{I<:CartesianIndex{0}}(iter::CartesianRange{I}, state) = iter.start, true
 done{I<:CartesianIndex{0}}(iter::CartesianRange{I}, state) = state
 
-@generated function length{I<:CartesianIndex}(iter::CartesianRange{I})
+@generated function size{I<:CartesianIndex}(iter::CartesianRange{I})
     N = length(I)
-    N == 0 && return 1
+    N == 0 && return ()
     args = [:(iter.stop[$i]-iter.start[$i]+1) for i=1:N]
-    Expr(:call,:*,args...)
+    Expr(:tuple,args...)
 end
 
+length(iter::CartesianRange) = prod(size(iter))
+
 last(iter::CartesianRange) = iter.stop
 
 @generated function simd_outer_range{I}(iter::CartesianRange{I})

base/regex.jl

@@ -327,6 +327,7 @@ compile(itr::RegexMatchIterator) = (compile(itr.regex); itr)
 eltype(::Type{RegexMatchIterator}) = RegexMatch
 start(itr::RegexMatchIterator) = match(itr.regex, itr.string, 1, UInt32(0))
 done(itr::RegexMatchIterator, prev_match) = (prev_match === nothing)
+iteratorsize(::Type{RegexMatchIterator}) = SizeUnknown()
 
 # Assumes prev_match is not nothing
 function next(itr::RegexMatchIterator, prev_match)

base/task.jl

@@ -253,6 +253,8 @@ function done(t::Task, val)
     istaskdone(t)
 end
 next(t::Task, val) = (t.result, nothing)
+iteratorsize(::Type{Task}) = SizeUnknown()
+iteratoreltype(::Type{Task}) = EltypeUnknown()
 
 isempty(::Task) = error("isempty not defined for Tasks")
 

test/simdloop.jl

@@ -104,17 +104,17 @@ end
 crng = CartesianRange(CartesianIndex{4}(2,0,1,3),
                       CartesianIndex{4}(4,1,1,5))
 indexes = simd_cartesian_range!(Array(eltype(crng), 0), crng)
-@test indexes == collect(crng)
+@test indexes == vec(collect(crng))
 
 crng = CartesianRange(CartesianIndex{2}(-1,1),
                       CartesianIndex{2}(1,3))
 indexes = simd_cartesian_range!(Array(eltype(crng), 0), crng)
-@test indexes == collect(crng)
+@test indexes == vec(collect(crng))
 
 crng = CartesianRange(CartesianIndex{2}(-1,1),
                       CartesianIndex{2}(-1,3))
 indexes = simd_cartesian_range!(Array(eltype(crng), 0), crng)
-@test indexes == collect(crng)
+@test indexes == vec(collect(crng))
 
 crng = CartesianRange(CartesianIndex{1}(2),
                       CartesianIndex{1}(4))
@@ -124,7 +124,7 @@ indexes = simd_cartesian_range!(Array(eltype(crng), 0), crng)
 crng = CartesianRange(CartesianIndex{0}(),
                       CartesianIndex{0}())
 indexes = simd_cartesian_range!(Array(eltype(crng), 0), crng)
-@test indexes == collect(crng)
+@test indexes == vec(collect(crng))
 
 # @simd with array as "range"
 # issue #13869

test/unicode/utf8proc.jl

@@ -244,7 +244,7 @@ let grphtest = (("b\u0300lahβlahb\u0302láh", ["b\u0300","l","a","h",
                     @test typeof(first(graphemes(s_))) == SubString{typeof(s_)}
                 end
                 grph = collect(graphemes(s_))
-                @test isempty(grph) || eltype(grph) == SubString{typeof(s_)}
+                @test eltype(grph) == SubString{typeof(s_)}
                 @test grph == g_
                 @test length(graphemes(s_)) == length(grph)
             end