Jacinda is a functional pattern filtering language, inspired by AWK.

Installation

Releases

There are binaries for some platforms on the releases page.

If you are on Mac, you will need to install *-librure.dylib as well.

Nix

Jacinda is available as a Nix package (thanks to Lukas Epple, who is the maintainer).

From Source

First, install Rust's regex library. You'll need to put librure.so or librure.dylib etc. in the appropriate place.

If you have cabal and GHC installed (perhaps via ghcup):

cabal install jacinda

Editor Support

There is a vim plugin and a VSCode extension.

Usefulness

Unix uses record separators in many places; we can display one entry in the PATH variable with:

echo $PATH | ja -F: "{|[x+'\n'+y]|>\`$}"

Many Unix tools output information separated with spaces. We use regular expressions to match relevant lines and then select the field with the data itself, viz.

otool -l $(locate libpng.dylib) | ja '{`1 ~ /^name/}{`2}'

To get the value of a variable (say, PATH) from the output of printenv:

printenv | ja -F= '{%/^PATH/}{`2}'

Documentation

See the guide (archived on Hackage, which contains a tutorial on some of the features as well as examples.

The manpages document the builtins and provide a syntax reference.

See the rosetta showing AWK alongside, or the [examples][./EXAMPLES.md] for its own capabilities.

Status

Missing Features & Bugs

• No nested dfns
• No list literal syntax
• Postfix :f and :i are handled poorly
• Streams of functions don't work
• Higher-order functions are subtly broken

Intentionally missing features:

• No loops

Advantages

• Rust's regular expressions
  • extensively documented with Unicode support
• Deduplicate builtin

Contributing

I have rewritten the code several times so forking and applying patches is fraught!

Bug reports are welcome contributions.