This repo tries to assess Rust arg parsing performance.

We currently compare:

See also an examination of design trade offs

Note: any non-performance comparison is meant to provide context for what you gain/lose with each crate's overhead. For a full comparison, see each parser docs

Name	Overhead (release)	Build (debug)	Parse (release)	Invalid UTF-8	Downloads	Version
null	0 KiB	399ms (full) 200ms (incremental)	3ms	Y	-	-
argh	35 KiB	4s (full) 237ms (incremental)	3ms	N		v0.1.8
bpaf	165 KiB	1s (full) 256ms (incremental)	5ms	Y		v0.6.0
bpaf_derive	160 KiB	7s (full) 256ms (incremental)	4ms	Y		v0.6.0
clap	607 KiB	4s (full) 467ms (incremental)	4ms	Y		v4.0.0
clap-minimal	417 KiB	3s (full) 380ms (incremental)	4ms	Y		v4.0.0
clap_derive	637 KiB	10s (full) 501ms (incremental)	4ms	Y		v4.0.0
clap_lex	37 KiB	759ms (full) 229ms (incremental)	3ms	Y		v0.3.0
gumdrop	33 KiB	4s (full) 233ms (incremental)	3ms	N		v0.8.1
lexopt	36 KiB	591ms (full) 217ms (incremental)	3ms	Y		v0.2.1
pico-args	28 KiB	583ms (full) 215ms (incremental)	4ms	Y		v0.5.0
xflags	24 KiB	1s (full) 210ms (incremental)	3ms	Y		v0.2.4

System: Linux 5.4.0-104-generic (x86_64) w/ -j 8

rustc: rustc 1.64.0 (a55dd71d5 2022-09-19)

Notes:

• Overhead will be lower if your application shares dependencies with your argument parsing library.

$ ./bench.py
$ ./format.py

To be included, the crate needs meet one of the following criteria:

• 10k+ recent downloads
• Unique API design

• RazrFalcon for creating the initial benchmarks
• djc for inspiration with template-benchmarks-rs
• sharkdp for hyperfine