Alias doesn't work for aptitude search in Eshell

Question

alias works very well in Eshell. I've used it like this:

alias sau sudo aptitude update

However, it doesn't work for the search command:

$ alias aps aptitude search 
$ aps emacs
search: You must provide at least one search term

What's wrong with this?

Answer 1

In short: use alias aps 'aptitude search $*' (quotes seem to be important).

The comment at the top of em-alias.el says the following.

Creating aliases

The user interface is simple: type alias followed by the command name followed by the definition. Argument references are made using $1, $2, etc., or $*. For example:

alias ll 'ls -l $*'

This will cause the command ll NEWS to be replaced by ls -l NEWS. This is then passed back to the command parser for reparsing.{Only the command text specified in the alias definition will be reparsed. Argument references (such as $*) are handled using variable values, which means that the expansion will not be reparsed, but used directly.}

To delete an alias, specify its name without a definition:

alias ll

Aliases are written to disk immediately after being defined or deleted. The filename in which they are kept is defined by the variable eshell-aliases-file.