Suggestion for more general/performant sentinel for find* functions

Internals & Design
5

You’re testing something nonsensical. The real tests are:

0.6:

julia> ff(z) = findfirst(x->x==z, "foobar") == 0
ff (generic function with 1 method)

julia> @btime ff($('z'))
  80.433 ns (0 allocations: 0 bytes)
true

0.7:

julia> ff(z) = findfirst(equalto(z), "foobar") == nothing
ff (generic function with 1 method)

julia> @btime ff($('z'))
  39.565 ns (0 allocations: 0 bytes)
true