1 unstable release
|0.1.0||Nov 5, 2018|
#12 in #arguments
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Traits and implementations for parsing command-line arguments.
This crate provides traits and implementations for parsing command-line arguments.
The core of the crate is
ParseArg trait. It works much like
FromStr trait, but with
- It operates on
&str, thus allowing wider range of possible inputs.
- It provides
parse_owned_arg()method which can be specialized to avoid allocations.
- It requires the implementor to provide
describe_type()to print human-readable description. of expected input.
- It requires the error type to implement
Displayin order to enable user-friendly interface.
Further, the crate provides
ParseArgFromStr trait, which causes any type implementing it to
ParseArg trait. This is handy when implementing
ParseArg for types that
FromStr implemented, so that boilerplate is reduced.
Since matching both
--foo VAL and
--foo=VAL arguments is common and it's not an easy task to
implement on top of
OsStr, due to limitation of
std, this crate also provides a function to
match and parse such arguments.
I will merge new implementations liberally, provided these conditions are met:
- The type is either in
stdor in another crate which is added as an optional dependency.
- The description of the type is gramatically correct, readable explanation of the type, that can be appended to the string "The input must be " without sounding unnatural.
- The user must be able to know how to formt the input based on the description without any googling. In case of doubt provide more precise description in parentheses.
- Your contribution is licensed under MIT or MITNFA license.