Mailing List Archives
Authenticated access
|
|
|
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [HTCondor-users] class ad logic with undef (non-)equal
- Date: Wed, 12 May 2021 10:18:46 -0500 (CDT)
- From: Todd L Miller <tlmiller@xxxxxxxxxxx>
- Subject: Re: [HTCondor-users] class ad logic with undef (non-)equal
So, one question would be, if there is a `?`-like operator for a boolean
non-equal comparison, that resolves in false when compared to undef?
If I understood your question correctly, you could also rewrite
your expression with =!=, it would seem:
( Expr1 || regexp(MyAttr, "strfoo") ) =!= true
# an undefined left-hand side is false
$ classad_eval '' '(False || regexp(MyAttr, "strfoo")) =!= True'
[ ]
true
# confirm that a non-matching string results in true
$ classad_eval 'MyAttr = "strbar"' '(False || regexp(MyAttr, "strfoo")) =!= True'
[ MyAttr = "strbar" ]
true
# confirm that a matching string results in false
$ classad_eval 'MyAttr = "strfoo"' '(False || regexp(MyAttr, "strfoo")) =!= True'
[ MyAttr = "strfoo" ]
false
-- ToddM