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(elisp)Hash Access

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Hash Table Access
=================

   This section describes the functions for accessing and storing
associations in a hash table.

 - Function: gethash key table &optional default
     This function looks up KEY in TABLE, and returns its associated
     VALUE--or DEFAULT, if KEY has no association in TABLE.

 - Function: puthash key value table
     This function enters an association for KEY in TABLE, with value
     VALUE.  If KEY already has an association in TABLE, VALUE replaces
     the old associated value.

 - Function: remhash key table
     This function removes the association for KEY from TABLE, if there
     is one.  If KEY has no association, `remhash' does nothing.

 - Function: clrhash table
     This function removes all the associations from hash table TABLE,
     so that it becomes empty.  This is also called "clearing" the hash
     table.

 - Function: maphash function table
     This function calls FUNCTION once for each of the associations in
     TABLE.  The function FUNCTION should accept two arguments--a KEY
     listed in TABLE, and its associated VALUE.