pretty printing for BlockInterlacer and CachedIterator (#411)

* pretty printing for BlockInterlacer and CachedIterator

* Add tests

* update tests

* int vectors in BlockInterlacer

Author: jishnub

src/LinearAlgebra/helper.jl

@@ -537,6 +537,10 @@ end
 CachedIterator{T,IT}(it::IT, state) where {T,IT} = CachedIterator{T,IT}(it,T[],state,0)
 CachedIterator(it::IT) where IT = CachedIterator{eltype(it),IT}(it, ())
 
+function Base.show(io::IO, c::CachedIterator)
+    print(io, "Cached ", c.iterator, " with ", c.length, " stored elements, and state = ", c.state)
+end
+
 function resize!(it::CachedIterator{T},n::Integer) where {T}
     m = it.length
     if n > m
@@ -668,12 +672,12 @@ conv(x::AbstractFill, y::AbstractFill) = DSP.conv(x, y)
 # TODO: cache sums
 
 
-struct BlockInterlacer{DMS<:Tuple}
+struct BlockInterlacer{DMS<:Tuple{Vararg{AbstractVector{Int}}}}
     blocks::DMS
 end
 
 
-const TrivialInterlacer{d} = BlockInterlacer{<:NTuple{d,Ones}}
+const TrivialInterlacer{d} = BlockInterlacer{<:NTuple{d,Ones{Int}}}
 
 BlockInterlacer(v::AbstractVector) = BlockInterlacer(Tuple(v))
 
@@ -685,6 +689,8 @@ length(b::BlockInterlacer) = mapreduce(sum,+,b.blocks)
 
 Base.IteratorSize(::Type{BlockInterlacer{T}}) where {T} = _IteratorSize(T)
 
+Base.show(io::IO, B::BlockInterlacer) = print(io, BlockInterlacer, "(", B.blocks, ")")
+
 # the state is always (whichblock,curblock,cursubblock,curcoefficients)
 # start(it::BlockInterlacer) = (1,1,map(start,it.blocks),ntuple(zero,length(it.blocks)))
 

test/show.jl

@@ -67,4 +67,10 @@
 			@test startswith(s, "ConstantOperator")
 		end
 	end
+	@testset "Iterators" begin
+		B = ApproxFunBase.BlockInterlacer((Ones{Int}(2), Ones{Int}(2)))
+		@test repr(B) == "ApproxFunBase.BlockInterlacer((Ones(2), Ones(2)))"
+		C = cache(B)
+		@test contains(repr(C), "Cached " * repr(B))
+	end
 end