Hashtables

Association lists are linear and slow. For larger sets of associations, hashtables tend to be much faster.

> (let ((h (make-hash-table)))

(defun get-h (key) (gethash key h))

(defun put-h (key value)

(setf (gethash key h) value))

)

PUT-H

> (put-h 'x 'y)

Y

> (get-h 'x)

Y ; The value associated with X

T ; True, there is a value.

>

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