Yash, yet another shell, is a POSIX-compliant command line shell.
Yash is intended to be the most POSIX-compliant shell in the world
while supporting features for daily interactive and scripting use.
Notable features are:
* Global aliases
* Arrays
* Socket redirection, pipeline redirection, and process redirection
* Brace expansion and extended globbing
* Fractional numbers in arithmetic expansion
* Prompt command and command-not-found handler
* Command line completion with predefined completion scripts for more
  than 100 commands
* Command line prediction based on command history