Identifiers - MIT/GNU Scheme 7.7.90+
Description: MIT/GNU Scheme 7.7.90+

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#### 1.3.3 Identifiers

An identifier is a sequence of one or more non-delimiter characters. Identifiers are used in several ways in Scheme programs:

- An identifier can be used as a variable or as a syntactic keyword.
- When an identifier appears as a literal or within a literal, it denotes a symbol.

Scheme accepts most of the identifiers that other programming languages allow. MIT/GNU Scheme allows all of the identifiers that standard Scheme does, plus many more.

MIT/GNU Scheme defines a potential identifier to be a sequence of non-delimiter characters that does not begin with either of the characters # or ,. Any such sequence of characters that is not a syntactically valid number (see Numbers) is considered to be a valid identifier. Note that, although it is legal for # and , to appear in an identifier (other than in the first character position), it is poor programming practice.

Here are some examples of identifiers:

         lambda             q
         list->vector       soup
         +                  V17a
         <=?                a34kTMNs
         the-word-recursion-has-many-meanings