ash software package provides compatibility package for dash, you can install in your Debian 7 (Wheezy) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install ash
ash is installed in your system.
Make ensure the ash package were installed using the commands given below,
$ sudo dpkg-query -l | grep ash *
You will get with ash package name, version, architecture and description in a table
| Distro | Debian 7 wheezy |
| Section | Shells |
| Package | ash |
| Version | 0.5.7-3 |
| Description | compatibility package for dash |
| Sub Section | Shells |