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Possible misuse of idempotent in HTML 4.0 December para 17.13.1

From: David J Woolley <djw@bts.co.uk>
Date: Thu, 5 Mar 1998 19:32:40 +0100
Message-Id: <199803051929.TAA15604@saracen.bts.co.uk>
To: www-html-editor@w3.org
17.13.1 Form submission method
The method attribute of the FORM element specifies the HTTP method used to send the form to the
processing agent. This attribute may take two values:
get: With the HTTP "get" method, the form data set [p.233] is appended to the URI specified by
the action attribute and this new URI is sent to the processing agent.
post: With the HTTP "post" method, the form data set [p.233] is included in the body of the form
and sent to the processing agent.
The "get" method should be used when the form is idempotent (i.e., causes no side-effects). Many
                                                 ^^^^^^^^^^

   This is not my understanding of idempotent, and I believe the parenthesized definition
   better matches the intended meaning.

   I understand idempotent to mean that a repeat of the operation results in no further
   change, but that the first use may produce side effects.  I.e set the thermostat to 20
   degrees C is idempotent, turn it up 5 degrees is not, and tell me what it is set to
   is the sort of operation that can safely be done with GET.
database searches have no visible side-effects and make ideal applications for the "get" method.

-- 
David Woolley - Office: David Woolley <djw@bts.co.uk>
BTS             Home: <david@djwhome.demon.co.uk>
Wallington      TQ 2887 6421
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Received on Thursday, 5 March 1998 14:44:32 GMT

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