An identifier uniquely distinguishes a variable, a procedure, a data type or any other ATEasy object. Identifiers are 1 to 256 characters in length. The general rule is that the first character must be alphabetic or an underscore, and the remaining characters must all be alphabetic, numeric, or an underscore. The one exception is command names, where the first character is allowed to be numeric.
ATEasy's comparison of identifiers is case-insensitive, that is, the upper-case alphabetic characters are considered to be the same characters as their equivalent lower-case characters. For example, the characters, XYX, xyz, and XyZ are all considered to be the same identifier.
Adopting a uniform approach to case is recommended. Also, all uses of the same identifier should use the same upper-case or lower-case pattern and not rely on case-insensitivity.