chickadee » persistent-hash-map » map-ref

map-ref map key #!optional not-foundprocedure

Returns the value associated with key in map or not-found (default #f) if key does not exist.

Example:

(define m (persistent-map 'foo 1))

(map-ref m 'foo 2) => 1
(map-ref m 'bar)   => #f
(map-ref m 'bar 2) => 2