On 12/21/2013 7:21 AM, John Gilmore wrote:
What you and Bernd say is correct but irrelevant, indeed misconceived.
o What happens if the user provides a syntactically incorrect label?
o What happens if the positional parameter R1 has the value 'gubbins'?
o Etc., etc.?
EJ's exemplary skeletal macro and my variation on it contain no
bulletin proofing of the [again skeletal] form
|&in setb (t'&label ne 'O') --value supplied?
| aif (&in).label_in --if so, examine it
|&abort setb 1 --set quit switch
| mnote . . .
| . . .
| ago .after_label
|.label_in anop
| ASYMBCHK candidate=&label, . . .
|. . .
|.after_label
but an example of this sort, intended to illustrate a method briefly,
is not the place for such code. We all, I must presume, know how to
write it and do write it in our production macro definitions.
John Gilmore, Ashland, MA 01721 - USA
Nonsense!
Ed's macro assembles correctly whether or not
a label is supplied, your version does not.
Neither version is bullet proof, but Ed's works
in both cases of a label supplied or not (neither
of which is an error, so 'bullet proofing' for
a missing label is really irrelevant).
--
Kind regards,
-Steve Comstock
The Trainer's Friend, Inc.
303-355-2752
http://www.trainersfriend.com
* We are going out of business effective 30 December, 2013
* To purchase a set of our training materials at terrific prices,
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Further, if the invoker supplies an invalid label
the Assembler will point that out in both versions.
