Also, going off of the benchmarks provided by @Roger-luo in his Comonicon post, ArgMacros v0.2.2 (inline) is (just barely) faster than the latest releases of any of the other options demonstrated:
[zachary@ZACHARY-PC argstest]$ hyperfine "julia example/argparse.jl 2"
Benchmark #1: julia example/argparse.jl 2
Time (mean ± σ): 3.819 s ± 0.018 s [User: 3.859 s, System: 0.828 s]
Range (min … max): 3.789 s … 3.848 s 10 runs
[zachary@ZACHARY-PC argstest]$ hyperfine "julia example/comonicon.jl 2"
Benchmark #1: julia example/comonicon.jl 2
Time (mean ± σ): 1.181 s ± 0.033 s [User: 1.243 s, System: 0.672 s]
Range (min … max): 1.134 s … 1.256 s 10 runs
[zachary@ZACHARY-PC argstest]$ hyperfine "julia example/fire.jl 2"
Benchmark #1: julia example/fire.jl 2
Time (mean ± σ): 836.2 ms ± 5.4 ms [User: 1.069 s, System: 0.633 s]
Range (min … max): 829.2 ms … 847.1 ms 10 runs
[zachary@ZACHARY-PC argstest]$ hyperfine "julia example/comonicon_zero.jl 2"
Benchmark #1: julia example/comonicon_zero.jl 2
Time (mean ± σ): 623.4 ms ± 12.8 ms [User: 834.2 ms, System: 617.9 ms]
Range (min … max): 614.4 ms … 656.3 ms 10 runs
[zachary@ZACHARY-PC argstest]$ hyperfine "julia example/argmacros.jl 2"
Benchmark #1: julia example/argmacros.jl 2
Time (mean ± σ): 580.0 ms ± 4.6 ms [User: 844.8 ms, System: 647.0 ms]
Range (min … max): 575.7 ms … 591.4 ms 10 runs