shellexpand, a library for shell-like expansion in strings

NOTE: THIS CRATE NAME IS RETIRED. There will no further updates beyond 2.1.2. Please switch to shellexpand, which will continue to be developed.

shellexpand is a single dependency library which allows one to perform shell-like expansions in strings, that is, to expand variables like $A or ${B} into their values inside some context and to expand ~ in the beginning of a string into the home directory (again, inside some context).

This crate provides generic functions which accept arbitrary contexts as well as default, system-based functions which perform expansions using the system-wide context (represented by functions from std::env module and dirs crate).

Note: This package was a fork of Vladimir Matveev's library. This fork existed due to a hiatus in maintenance. Please use shellexpand instead now.

Alternatives to this crate:

• expanduser: Tilde substitution only. Supports ~user which this crate currently does not (although we hope to).
• envsubst: Does not do offer tildeexpansion. Only supports certain concrete types (eg HashMap for variable map).
• expand_str: Uses %..% syntax. Does not offer tilde expansion. Variable lookups can only be infallible.
• tilde_expand: Only does tilde expansion, on bytes ([u8]).

Usage

Add a dependency in your Cargo.toml.

To avoid having to write use shellexpand_fork as shellexpand or similar, rename the package on import:

[dependencies]
shellexpand = { version = "2.1", package = "shellexpand-fork" }

See the crate documentation (a link is present in the beginning of this readme) for more information and examples.

Changelog

Version 2.1.2

Minor changes:

• README: direct people back to shellexpand
• List alternatives to this crate.
• Switch back to dirs from dirs-next.
• Improve linking in docs and fix broken links and badges.
• Apply some proposals from cargo fix.

Version 2.1.1

• Fix tilde expanding on Windows with Windows style (backslash) paths. Addresses https://github.com/netvl/shellexpand/pull/13.
• Forked as shellexpand-fork on crates.io.

Version 2.1.0

• Switched to dirs-next instead of the obsolete dirs as the underlying dependency used to resolve the home directory
• Switched to GitHub Actions instead of Travis CI for building the project.

Version 2.0.0

• Added support for default values in variable expansion (i.e. ${ANSWER:-42})
• Breaking changes (minimum Rust version is now 1.30.0):
  • Using dyn for trait objects to fix deprecation warning
  • Switched to using source() instead of cause() in the Error implementation, and therefore added a 'static bound for the generic error parameter E

Version 1.1.1

• Bump dirs dependency to 2.0.

Version 1.1.0

• Changed use of deprecated std::env::home_dir to the dirs::home_dir function

Version 1.0.0

• Fixed typos and minor incompletenesses in the documentation
• Changed home_dir argument type for tilde expansion functions to FnOnce instead FnMut
• Changed LookupError::name field name to var_name

Version 0.1.0

• Initial release

License

This program is licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.