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Re: membership test problem

From: Mike Mason <mmlnx at us dot ibm dot com>
To: "Frank Ch. Eigler" <fche at redhat dot com>
Cc: SystemTAP <systemtap at sources dot redhat dot com>
Date: Thu, 26 Oct 2006 17:49:23 -0700
Subject: Re: membership test problem
References: <45412068.5090809@us.ibm.com> <y0miri6smxi.fsf@ton.toronto.redhat.com>

I vote to change it. The current behavior isn't intuitive. I have a script where I have to add one to the integer elements to workaround the problem, then subtract one later when I use the values. Kinda kludgey.

- Mike

Frank Ch. Eigler wrote:

Mike Mason <mmlnx@us.ibm.com> writes:

What should the following code print?  I expected TRUE, but got
FALSE.  Looks like if the array element value is 0, the membership
test fails.  Is this correct? [...]


Yes, Josh's explanation is correct, zero and "" are deemed to be
null/absent values for purposes of array elements.  (This could change
though.)

(I could have sworn that I documented this behavior in the man page,
but now I can't find it.  It is in the tutorial.)

- FChE

References:
- membership test problem
  - From: Mike Mason
- Re: membership test problem
  - From: Frank Ch. Eigler

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