broadcast_fuse.jl

broadcast_fuse(types::Type, f) = f
broadcast_fuse(types::Type, f, fs...) = x -> f(broadcast_fuse(types, fs...)(x))

a(x) = x+1
b(x) = x*x

f1(x) = broadcast_fuse(Array, a, b)(x) # Needed so that the compiler treats anonymous function as const
@code_warntype f1(1)
@code_native f1(1)

f2(x) = a(b(x))
@code_warntype f2(1)
@code_native f2(1)

f3(x) = broadcast(f2, x)
@code_warntype f3(1)
@code_native f3(1)

using BenchmarkTools
@benchmark f1(1)
@benchmark f2(1)
@benchmark f3(1)