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From: weiner@novavax.UUCP (Bob Weiner)
Newsgroups: comp.lang.eiffel
Subject: Problem with semantics of 'put' in Eiffel library class LINKED_LIST
Message-ID: <1749@novavax.UUCP>
Date: 19 Jan 90 23:30:19 GMT
Organization: Motorola Inc.
Lines: 24

This note refers to V2.2B of ISE's Eiffel libraries.

I have a problem with the semantics of the LINKED_LIST 'put' operation.
I believe they should be different.  Specifically, a list put should be
an insertion rather than a replacement operation as it presently is.
(Presently 'put_left' and 'put_right' must be used for insertion.)  I
propose that 'put' should be the same as 'put_left' and the operation
that 'put' now performs should be renamed 'replace' for clarity.

Any housewife or professional programmer knows that putting something
into a list does not eliminate any of the other list items, hence the
need for the change.  Additionally, the current semantics conflicts with
the 'put' of SORTED_LIST which is an insert operation.

ARRAY put operations do replace the item indexed in the array but this
is what one would naturally expect and bears no relation to the best
semantics for a LIST put.

I am very surprised that no one else has mentioned this but I think it
is important since programmers can too easily overrite LIST elements.

-- 
Bob Weiner, Motorola, Inc.,   USENET:  ...!gatech!uflorida!novavax!weiner
(407) 364-2087