#666 TRACE R may trace too much

[Bob Coleman]

Version of ooRexx: 4.0 beta subversion 4567.

Operating System: Windows XP Home Edition SP3

Contact details: rcoleman0@gmail.com

I'm not certain whether this is a bug or something that I don't understand.

I previously reported (bug 2782557) that TRACE R didn't trace the results of PARSE instructions.

This was supposed to have been fixed in build 4535. A comment was made that the behavior had also been enhanced such that the parsed string is traced.

Now in build 4567, I see that this is all true, but the parsed string seems to be traced twice in most cases.

The following comments are based on the attached TRACEFAIL.REX being invoked as

tracefail a b c d

The trace of the "parse arg" instruction consists of a null string followed by the argument string "a b c d" followed by each of the letters assigned to a1, a2, and a3. I don't understand the reason for the null string. This null string here is why I said above that the parsed string seems to be traced twice in MOST cases. In the following TRACE instructions in TRACEFAIL.REX, the string actually seems to be shown twice rather than shown once following the showing of a null string. For example

Parse var data d1 d2

shows

a b
a b
a
b

It's possible that all this is intended behavior, but it's confusing to me.

[Bob Coleman]

Illustrate possible incorrect output from TRACE R instruction

[Rick McGuire]

Yes, you're correct...the code added to trace the string being parsed accidentally ended up tracing it twice.

Committed revision 4571.

[Mark Miesfeld]

The fix for this item was in the 4.0.0 release.