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A name in its simplest form is a letter followed by zero or more letters, digits, underscore characters (_) and question marks (?), with lowercase and uppercase letters distinct.  The maximum length of a name is system dependent. On 32-bit platforms, it is 268,435,439 characters; on 64-bit platforms, it is 34,359,738,335 characters.


There are two types of names: indexed names and symbols (non-indexed names).


Any expression can be assigned to a name. If no value has been assigned to the name, then it stands for itself.


Names can be formed with the concatenation operator || or with the function cat. For more information, see the help page for cat.


A variable name beginning with _Env is considered an environment variable.


Names that start with an underscore (with the exception of _Env) are used as global variable names by Maple and are effectively reserved for use by library code. Do not use a symbol beginning with an underscore. The empty name `` must never be assigned a value. Failure to follow these rules can lead to unexpected results.


Names containing a slash (/) are generally reserved for use by library code and should not be assigned a value unless explicitly recommended on a help page.


Names that end with a tilde (~) are used by Maple to denote variables with assumptions on them and therefore should also be avoided by users.


Names that start with a tilde are used by the Maple spreadsheet component.  The tilde can be followed by a sequence of alphanumeric, underscore, or dollar sign characters.


A name may also be formed by enclosing any sequence of characters in a pair of left single quotes (` `). For example: `This is a name!` := 1.


Any valid Maple name formed without using left single quotes is precisely the same as the name formed by surrounding the name with left single quotes.  Therefore, x and `x` both refer to the same name x. However, a keyword may not be used as a name unless it is enclosed in left single quotes.


In some previous releases of Maple, names formed by using left single quotes were used as character strings instead of names. A common example was the string used as an error message, for example,  ERROR(`the argument must be an integer`). This use of names has been made obsolete by the addition of the string type in Maple.


Two successive left single quotes that appear after the opening of a name are parsed as a single left single quote.  Thus,  `abc``de` yields abc`de. Alternatively, a left single quote can be written within a name by preceding it with a backslash (\ ), for example, `abc\`de`.


The type function understands the type names symbol and indexed, and the type name is defined to be either of symbol or indexed.


A symbol can be converted into a string by using convert(aSymbol, string). Likewise, a string can be converted into a symbol by using convert(aString, symbol). Alternatively, one can use convert(aString, name).

See Also