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Function `copy-symbol`

Syntax:

copy-symbol symbol &optional copy-properties → new-symbol

Arguments and Values:

symbol—a symbol.

copy-properties—a generalized boolean. The default is false.

new-symbol—a fresh, uninterned symbol.

Description:

10.3.0 8 copy-symbol returns a fresh, uninterned symbol, the name of which is string= to and possibly the same as the name of the given symbol.

If copy-properties is false, the new-symbol is neither bound nor fbound and has a null property list. If copy-properties is true, then the initial value of new-symbol is the value of symbol, the initial function definition of new-symbol is the functional value of symbol, and the property list of new-symbol is a copy₂ of the property list of symbol.

Examples:

 (setq fred 'fred-smith) → FRED-SMITH
 (setf (symbol-value fred) 3) → 3
 (setq fred-clone-1a (copy-symbol fred nil)) → #:FRED-SMITH
 (setq fred-clone-1b (copy-symbol fred nil)) → #:FRED-SMITH
 (setq fred-clone-2a (copy-symbol fred t))   → #:FRED-SMITH
 (setq fred-clone-2b (copy-symbol fred t))   → #:FRED-SMITH
 (eq fred fred-clone-1a) → false
 (eq fred-clone-1a fred-clone-1b) → false
 (eq fred-clone-2a fred-clone-2b) → false
 (eq fred-clone-1a fred-clone-2a) → false
 (symbol-value fred) → 3
 (boundp fred-clone-1a) → false
 (symbol-value fred-clone-2a) → 3
 (setf (symbol-value fred-clone-2a) 4) → 4
 (symbol-value fred) → 3
 (symbol-value fred-clone-2a) → 4
 (symbol-value fred-clone-2b) → 3
 (boundp fred-clone-1a) → false
 (setf (symbol-function fred) #'(lambda (x) x)) → #<FUNCTION anonymous>
 (fboundp fred) → true
 (fboundp fred-clone-1a) → false
 (fboundp fred-clone-2a) → false

Side Effects:

None.

Affected By:

None.

Exceptional Situations:

Should signal an error of type type-error if symbol is not a symbol.

Notes:

Implementors are encouraged not to copy the string which is the symbol's name unnecessarily. Unless there is a good reason to do so, the normal implementation strategy is for the new-symbol's name to be identical to the given symbol's name.

Barrett: This is only true if the implementation of MAKE-SYMBOL doesn't copy, which it might. \code (copy-symbol \param{x} nil) \EQ (make-symbol (symbol-name \param{x})) \endcode