Boolean short circuit "fusion"

General Usage
20

After reading that issue I had some inspiration -

@inline _lazy(x) = x[1]  # unwrap the tuple
@inline Broadcast.broadcasted(::typeof(_lazy), x) = (x,)  # wrap the Broadcasted object in a tuple to avoid materializing
macro lazy(x)
	return esc(:(_lazy(_lazy.($x))))
end

Which gives

julia> a = rand(10000) ; b = rand(10000) ;

julia> @btime sum(a .+ b)
  10.896 μs (5 allocations: 78.27 KiB)
9902.652963666198

julia> @btime sum(@lazy a .+ b)
  13.095 μs (3 allocations: 64 bytes)
9902.652963666245

julia> @btime any(a .+ b .> 1.9)
  15.549 μs (7 allocations: 5.64 KiB)
true

julia> @btime any(@lazy a .+ b .> 1.9)
  1.016 μs (4 allocations: 96 bytes)
true

So not materializing the array isn’t always faster (depends on the operation) but it does save on allocations.

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