Iterator over Floats

Specific Domains Numerics
1

So I’ve been working on special functions, and to help with that I’ve created this class that implements an Iterator of Float values.

struct FloatIterator{T}<:AbstractVector{T}
    min::T
    max::T
    FloatIterator{T}(min, max) where T = min > max ? error("max less than min") : new{T}(min,max)
end
FloatIterator{T}() where T =FloatIterator{T}(T(-Inf),T(Inf))
Base.iterate(it::FloatIterator) = (it.min, nextfloat(it.min))
function Base.iterate(it::FloatIterator{T}, el) where T
    return el == it.max ? nothing : (el, nextfloat(el))
end
function Base.size(it::FloatIterator{T}) where T
    if isless(it.max, 0.0)
        size = reinterpret(Base.uinttype(T), it.max) - reinterpret(Base.uinttype(T), it.min)
    elseif isless(-0.0, it.min)
        size = reinterpret(Base.uinttype(T), it.max) - reinterpret(Base.uinttype(T), it.min)
    else
        size  = reinterpret(Base.uinttype(T), it.max)
        size += reinterpret(Base.uinttype(T), it.min) - reinterpret(Base.uinttype(T), T(-0.0))
    end
    return (size+1,)
end
Base.getindex(it::FloatIterator{T}, i::Int) where T = nextfloat(it.min, i-1)
Base.show(io::IO, mime::MIME"text/plain", it::FloatIterator) =  show(io, it)
Base.show(io::IO, it::FloatIterator) = print(io, "FloatIterator(", it.min, ", ", it.max, ")")

It takes about 330μs to loop through all Float16, and 24s to loop through all Float32.

Let me know if you think this should end up in a package somewhere or if similar functionality already exists!

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2

for convenience, unless it goes against best Iterator API practice

FloatIterator(min::T, max::T) where T = FloatIterator{T}(min, max)
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