An ultra simple CLI arguments parser.
If you think that this library doesn't support some feature, it's probably intentional.
- No help generation.
- Only flags, options, free arguments and subcommands are supported.
- No combined flags (like
-vvv
or-abc
). - Options can be separated by a space,
=
or nothing. See build features. - Arguments can be in any order.
- Non UTF-8 arguments are supported.
-
eq-separator
Allows parsing arguments separated by
=
. Enabled by default.
This feature adds about 1KiB to the resulting binary. -
short-space-opt
Makes the space between short keys and their values optional (e.g.
-w10
).
Ifeq-separator
is enabled, then it takes precedence and the '=' is not included.
Ifeq-separator
is disabled, then-K=value
gives an error instead of returning"=value"
.
The optional space is only applicable for short keys because--keyvalue
would be ambiguous.
The core idea of pico-args
is to provide some "sugar" for arguments parsing without
a lot of overhead (binary or compilation time wise).
There are no point in comparing parsing features since pico-args
supports
only the bare minimum. So we will compare only the size overhead and compilation time.
There are a lot of arguments parsing implementations, but we will use only these one:
- clap - is the most popular and complete one
- gumdrop - a simple parser that uses procedural macros
- structopt - a two above combined
- argh - similar to gumdrop
null | pico-args |
clap |
gumdrop |
structopt |
argh |
|
---|---|---|---|---|---|---|
Binary overhead | 0KiB | 14.3KiB | 373.0KiB | 19.8KiB | 371.4KiB | 17.6KiB |
Build time | 0.4s | 0.7s | 5.6s | 4.1s | 6.2s | 4.0s |
Number of dependencies | 0 | 0 | 8 | 5 | 20 | 8 |
Tested version | - | 0.4.0 | 2.33.3 | 0.8.0 | 0.3.21 | 0.1.4 |
- Binary size overhead was measured by subtracting the
.text
section size of an app with arguments parsing and a hello world app. - Build time was measured using
hyperfine 'cargo clean; cargo build --release'
. - Test projects can be found in
test-apps/
.
MIT