"Paul Gilmartin" <[email protected]> wrote in message news:<listserv%[email protected]>... > On Tue, 6 Jul 2010 06:54:54 -0700, Charles Mills wrote: > > >It seems to me that it is JCL's "job" to catch the error because the writer > >of the PROC has no opportunity to do so. It's an obvious opportunity for a > >"dumb user" error -- and it's the job of the "system" (broadly defined to > >include JCL, the sysprog who wrote the PROC, etc.) to diagnose it. Quibbling > >about syntax versus semantics does not help the user mystified why his JCL > >change did not have any apparent affect. The assembler macro facility -- > >which uses a syntax that is obviously a first cousin to the JCL PROC > >facility -- would catch the error at the macro invocation level. > > > It's a prevalent habit of coders to exploit naive parameter list > parsers by writing scripts which simply append overriding key/value > pairs to the end of a default parameter string. > > Historically, Linkage Editor and Assembler H permitted this in PARM > strings, allowing the later value of the keyword to prevail. With > the advent of Binder (IIRC; perhaps it was HLASM; perhaps both), > duplicate keys in the PARM string were treated as errors. This was > swiftly reverted to the earlier behavior, likely by APAR. > > But JCL differs from the mode in using the earlier value rather than > the later. > > -- gil >
And then there is also the parsing of parmlib members, where a parameter can occur multiple times in one member or multiple times in several sequentially processed members (IEASYSxx). The rules are as diverse as possible: select the first value, select the last value, add the values of all occurances of the parameter or not accept multiple occurances of a parameter. So you are subjected to the applicatin coder's view on what is desirable. Kees. ******************************************************** For information, services and offers, please visit our web site: http://www.klm.com. This e-mail and any attachment may contain confidential and privileged material intended for the addressee only. If you are not the addressee, you are notified that no part of the e-mail or any attachment may be disclosed, copied or distributed, and that any other action related to this e-mail or attachment is strictly prohibited, and may be unlawful. If you have received this e-mail by error, please notify the sender immediately by return e-mail, and delete this message. Koninklijke Luchtvaart Maatschappij NV (KLM), its subsidiaries and/or its employees shall not be liable for the incorrect or incomplete transmission of this e-mail or any attachments, nor responsible for any delay in receipt. Koninklijke Luchtvaart Maatschappij N.V. (also known as KLM Royal Dutch Airlines) is registered in Amstelveen, The Netherlands, with registered number 33014286 ******************************************************** ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
