CLHS: Function SYMBOL-PACKAGE

#

Function SYMBOL-PACKAGE

Syntax:

symbol-package symbol => contents

Arguments and Values:

symbol---a symbol.

contents---a package object or nil.

Description:

Returns the home package of symbol.

Examples:

     (in-package "CL-USER") =>  #<PACKAGE "COMMON-LISP-USER">
     (symbol-package 'car) =>  #<PACKAGE "COMMON-LISP">
     (symbol-package 'bus) =>  #<PACKAGE "COMMON-LISP-USER">
     (symbol-package :optional) =>  #<PACKAGE "KEYWORD">
     ;; Gensyms are uninterned, so have no home package.
     (symbol-package (gensym)) =>  NIL
     (make-package 'pk1) =>  #<PACKAGE "PK1">
     (intern "SAMPLE1" "PK1") =>  PK1::SAMPLE1, NIL
     (export (find-symbol "SAMPLE1" "PK1") "PK1") =>  T
     (make-package 'pk2 :use '(pk1)) =>  #<PACKAGE "PK2">
     (find-symbol "SAMPLE1" "PK2") =>  PK1:SAMPLE1, :INHERITED
     (symbol-package 'pk1::sample1) =>  #<PACKAGE "PK1">
     (symbol-package 'pk2::sample1) =>  #<PACKAGE "PK1">
     (symbol-package 'pk1::sample2) =>  #<PACKAGE "PK1">
     (symbol-package 'pk2::sample2) =>  #<PACKAGE "PK2">
     ;; The next several forms create a scenario in which a symbol
     ;; is not really uninterned, but is "apparently uninterned",
     ;; and so SYMBOL-PACKAGE still returns NIL.
     (setq s3 'pk1::sample3) =>  PK1::SAMPLE3
     (import s3 'pk2) =>  T
     (unintern s3 'pk1) =>  T
     (symbol-package s3) =>  NIL
     (eq s3 'pk2::sample3) =>  T

Side Effects: None.

Affected By:

import, intern, unintern

Exceptional Situations:

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

See Also:

intern

Notes: None.

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