Node:Identifiers, Next:Comments, Up:Syntax

Identifiers

Identifiers are used to name things in a program.

An identifier consists of one or more of the following:

• A letter.
• A digit (0 though 9).
• The characters period (.) or underscore (_).
• Any character (except end of line) if it is preceeded by a backslash. For example: \- means the same as -, except that the - as thought of as a letter.

An identifier cannot start with a digit, nor can the second character be a digit if the first character is a period. This is because such words are parsed as numbers.

Note that the identifiers . and .. are reserved (they are used to access the filesystem).