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npm · #54 most downloaded on npm
CLI arguments parser. Native port of python's argparse.
Last release 24 days ago
10 Sep 2026
Ships unpredictably
gaps range from 2 weeks to 5.9 years
Nearly every release is documented
notes for 33 of 33 stable releases
Nothing withdrawn
no release was ever pulled
14 years old
33 releases · first in 2012
Aligned int and float conversion with Python: fixed negative zero for integers and accepted string formats for floats, #191.
int and float conversion with Python: fixed negative zero for
integers and accepted string formats for floats, #191.action: 'extend' to iterate over values and reject non-iterable values
as in Python, including splitting scalar strings into characters, #190.Adjusted attribution to PSF-2.0 (not a license change), #188.
One column per quarter.
Deprecation warnings for arguments and subcommands marked with deprecated.
color option.suggest_on_error.deprecated.argparse port from 3.9.0 to 3.14.6.type: 'auto'.
See the migration guide for replacements.Fix issue with process.argv when used with interpreters (coffee, ts-node, etc.), #150.
process.argv when used with interpreters (coffee, ts-node, etc.), #150.Full rewrite. Now port from python 3.9.0 & more precise following. See doc for difference and migration info.
Use .concat instead of + for arrays, #122.
Rerelease after 1.0.8 - deps cleanup.
Maintenance (deps bump, fix node 6.5+ tests, coverage report).
Teach addArgument to accept string arg names. #97, @tomxtobin.
addArgument to accept string arg names. #97, @tomxtobin.Maintenance: moved to eslint & updated CS.
Removed lodash dependency to significantly reduce install size. Thanks to @mourner.
Maintenance: lodash update to 4.0.0.
Fix parse = in args: --examplepath="C:\myfolder\env=x64". #84, @CatWithApple.
= in args: --examplepath="C:\myfolder\env=x64". #84, @CatWithApple.Relaxed lodash version dependency.
Changed dependencies to be compatible with ancient nodejs.
Replaced underscore with lodash.
underscore with lodash.Maintenance release. Updated dependencies and docs.
### Fixed - Fixed #55, @trebor89
### Fixed - Fixed #62, @maxtaco
Added .npmignore to reduce package size
.npmignore to reduce package sizeFixed conflictHandler (#46), @hpaulj
Added 70+ tests (ported from python), @hpaulj
Added mutual exclusion support, thanks to @hpaulj
storeConst & appendConst actions, thanks to @hpauljFixed option dest interferens with other options (issue #23), thanks to @hpaulj
* positionals, thanks to @hpauljgetDefault() behavior, thanks to @hpauljFixed parser parents (issue #19), thanks to @hpaulj
Fixed 'choices' argument parse (issue #16)
Fixed check for conflict of options (thanks to @tomxtobin)
Fix parser #setDefaults method (thanks to @tomxtobin)
Fixed pseudo-argument support (thanks to @CGamesPlay)
Fixed formatter api name: Formatter -> HelpFormatter
Removed excess whitespace in help
Fixed line wrapping in help formatter
[3.0.2]: https://github.com/nodeca/argparse/compare/3.0.1...3.0.2 [3.0.1]: https://github.com/nodeca/argparse/compare/3.0.0...3.0.1 [3.0.0]: https://g
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