[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Tables returning nil if no value
One thing that bothers me is that table-entries that have never been
defined return nil. I often want to discriminate between values that
have never been set and ones that have been set to nil. Shouldn't
uninitialized table-entries return some undefined value instead of nil?
The problem is that *any* value could be stored in the table, including
"some undefined value".
The correct solution is to return multiple values such as the following:
(table-entry table key) => found?, value
where found? is true if there was a <key,value> pair in the table and
value is undefined if found? is false.
Any votes for this system? Against?