Ahh, I think I was thinking about lists (as lists are the default ‘string’ type in erlang):
##### With input binary #####
Name ips average deviation median 99th %
guard_top 34.09 K 29.34 μs ±74.54% 28 μs 45 μs
guard_bot 30.61 K 32.67 μs ±74.42% 31 μs 48 μs
match_bot 22.81 K 43.85 μs ±35.95% 41 μs 78 μs
match_top 22.38 K 44.69 μs ±38.02% 43 μs 67 μs
Comparison:
guard_top 34.09 K
guard_bot 30.61 K - 1.11x slower
match_bot 22.81 K - 1.49x slower
match_top 22.38 K - 1.52x slower
##### With input list #####
Name ips average deviation median 99th %
match_bot 34.39 K 29.08 μs ±65.78% 28 μs 41 μs
guard_top 34.24 K 29.21 μs ±54.19% 28 μs 45 μs
match_top 31.49 K 31.75 μs ±61.61% 31 μs 46 μs
guard_bot 31.25 K 32.00 μs ±57.29% 31 μs 49 μs
Comparison:
match_bot 34.39 K
guard_top 34.24 K - 1.00x slower
match_top 31.49 K - 1.09x slower
guard_bot 31.25 K - 1.10x slower
##### With input not binary #####
Name ips average deviation median 99th %
guard_bot 31.18 K 32.07 μs ±63.11% 31 μs 44 μs
guard_top 31.15 K 32.10 μs ±58.90% 30 μs 50 μs
match_bot 29.16 K 34.30 μs ±38.15% 33 μs 49 μs
match_top 27.41 K 36.48 μs ±36.63% 35 μs 52 μs
Comparison:
guard_bot 31.18 K
guard_top 31.15 K - 1.00x slower
match_bot 29.16 K - 1.07x slower
match_top 27.41 K - 1.14x slower
Substantial performance difference on binaries though (a good 50% slower for match contexts)! And of course the list test is faster than the binary test regardless of how it is done (the BEAM is built for lists instead of binaries when processing them out). ^.^
EDIT: The code is about the same is @michalmuskala’s except the count is increased to 1000 to prevent fast function warnings and I added some tuple cases to each set (unmatched in all cases) with the string/list test being at the top or bottom of the tuple matchers as per the test name.
