[procedure] hash-table-ref hash-table key [thunk]

SRFI-69: This procedure returns the value associated to key in hash-table. If no value is associated to key and thunk is given, it is called with no arguments and its value is returned; if thunk is not given, an error is signalled.

[procedure] hash-table-ref hash-table key [default]

Chicken: if no entry is found, #f is returned. See also hash-table-set!.

This is called hash-table-get in some implementations.