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(cl)Creating Symbols

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Creating Symbols
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These functions create unique symbols, typically for use as temporary
variables.

 - Function: gensym &optional x
     This function creates a new, uninterned symbol (using
     `make-symbol') with a unique name.  (The name of an uninterned
     symbol is relevant only if the symbol is printed.)  By default,
     the name is generated from an increasing sequence of numbers,
     `G1000', `G1001', `G1002', etc.  If the optional argument X is a
     string, that string is used as a prefix instead of `G'.
     Uninterned symbols are used in macro expansions for temporary
     variables, to ensure that their names will not conflict with
     "real" variables in the user's code.

 - Variable: *gensym-counter*
     This variable holds the counter used to generate `gensym' names.
     It is incremented after each use by `gensym'.  In Common Lisp this
     is initialized with 0, but this package initializes it with a
     random (time-dependent) value to avoid trouble when two files that
     each used `gensym' in their compilation are loaded together.
     (Uninterned symbols become interned when the compiler writes them
     out to a file and the Emacs loader loads them, so their names have
     to be treated a bit more carefully than in Common Lisp where
     uninterned symbols remain uninterned after loading.)

 - Function: gentemp &optional x
     This function is like `gensym', except that it produces a new
     _interned_ symbol.  If the symbol that is generated already
     exists, the function keeps incrementing the counter and trying
     again until a new symbol is generated.

   The Quiroz `cl.el' package also defined a `defkeyword' form for
creating self-quoting keyword symbols.  This package automatically
creates all keywords that are called for by `&key' argument specifiers,
and discourages the use of keywords as data unrelated to keyword
arguments, so the `defkeyword' form has been discontinued.