## 18.4 ‘`@alias new=existing`’

The ‘`@alias`’ command defines a new command to be just like an existing one. This is useful for defining additional markup names, thus preserving semantic information in the input even though the output result may be the same.

Write the ‘`@alias`’ command on a line by itself, followed by the new command name, an equals sign, and the existing command name. Whitespace around the equals sign is ignored. Thus:

    @alias new = existing

For example, if your document contains citations for both books and some other media (movies, for example), you might like to define a macro `@moviecite{}` that does the same thing as an ordinary `@cite{}` but conveys the extra semantic information as well. You’d do this as follows:

    @alias moviecite = cite

Macros do not always have the same effect due to vagaries of argument parsing. Also, aliases are much simpler to define than macros. So the command is not redundant. (It was also heavily used in the Jargon File!)

Aliases must not be recursive, directly or indirectly.