# Boolean short circuit "fusion"

**URL:** https://discourse.julialang.org/t/boolean-short-circuit-fusion/19641
**Category:** General Usage
**Created:** [January 14, 2019, 10:33pm UTC](https://discourse.julialang.org/t/boolean-short-circuit-fusion/19641 "2019-01-14T22:33:10Z")
**Posts on this page:** 1
**Showing post:** 15

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### Author: ![dawbarton](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/dawbarton/32/215461_2.png) [@dawbarton](https://discourse.julialang.org/u/dawbarton)
#### Post date: [January 15, 2019, 1:28pm UTC](https://discourse.julialang.org/t/boolean-short-circuit-fusion/19641/15 "2019-01-15T13:28:25Z")

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I’ve wondered for a while whether it is possible to abuse the broadcast machinery to do something like this (basically to avoid `materialize` being called on the lazy broadcasted object). I’ve not found a nice way of doing it (i.e., a way that doesn’t obscure/muddy the semantics of dot broadcasting) but here is a not-so-nice way of doing it.

```julia
myany(x) = any(x) # avoid piracy!
Broadcast.broadcasted(::typeof(myany), x) = myany(x) # exploit the fact that the broadcasted object is iterable

```

On a simple test case this gives

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

julia> @btime any(($a .> 0.5) .& ($b .> 0.5) .& ($c .> 0.5))
  19.828 μs (3 allocations: 5.55 KiB)
true

julia> @btime myany.(($a .> 0.5) .& ($b .> 0.5) .& ($c .> 0.5))
  59.478 ns (10 allocations: 240 bytes)
true

```

So much faster than the original case but not as fast as the anonymous function or generator expression versions as mentioned above (and it allocates more).

```julia
julia> @btime any(((aa, bb, cc),) -> (aa > 0.5) && (bb > 0.5) && (cc > 0.5), zip($a, $b, $c))
  13.820 ns (2 allocations: 64 bytes)
true

julia> @btime any((aa > 0.5) && (bb > 0.5) && (cc > 0.5) for (aa, bb, cc) in zip($a, $b, $c))
  16.822 ns (3 allocations: 80 bytes)
true

```

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