From balld@webslingerZ.com  Wed Jan 10 02:54:59 2001
Return-Path: <balld@webslingerZ.com>
Mailing-List: contact cocoon-dev-help@xml.apache.org; run by ezmlm
Delivered-To: mailing list cocoon-dev@xml.apache.org
Received: (qmail 92739 invoked from network); 10 Jan 2001 02:54:59 -0000
Received: from rdu25-5-046.nc.rr.com (HELO akira.webslingerZ.com) (24.25.5.46)
  by h31.sny.collab.net with SMTP; 10 Jan 2001 02:54:59 -0000
Received: by akira.webslingerZ.com (Postfix, from userid 501)
	id BB42913032; Tue,  9 Jan 2001 21:56:05 -0500 (EST)
Received: from localhost (localhost [127.0.0.1])
	by akira.webslingerZ.com (Postfix) with ESMTP
	id 9A81E60B1; Tue,  9 Jan 2001 21:56:05 -0500 (EST)
Date: Tue, 9 Jan 2001 21:56:05 -0500 (EST)
From: Donald Ball <balld@webslingerZ.com>
X-Sender:  <balld@localhost.localdomain>
To: Vadim Gritsenko <vgritsenko@hns.com>
Cc: Robin Green <greenrd@hotmail.com>, <cocoon-dev@xml.apache.org>,
	<xsp-dev@xml.apache.org>
Subject: RE: [C2] xsp:logic tag behaviour
In-Reply-To: <NEBBKBNHBMFHDJPKGCOBIEBKCEAA.vgritsenko@hns.com>
Message-ID: <Pine.LNX.4.30.0101092152120.27724-100000@localhost.localdomain>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
X-Spam-Rating: h31.sny.collab.net 1.6.2 0/1000/N

On Tue, 9 Jan 2001, Vadim Gritsenko wrote:

> Sorry to hear this... But - correct me if I don't understand this -
> it is possible to re-write logicsheet so it uses variables only
> inside scope of <xsp:logic> tag, example:
> ------------- existing code --------------
>       <xsp:logic>
>         Stack esqlSessions = new Stack();
>         EsqlSession esqlSession = null;
>       </xsp:logic>
>       <xsl:apply-templates/>
> -------------- replace by ----------------
>       <xsp:logic>
>         Stack esqlSessions = new Stack();
>         EsqlSession esqlSession = null;
>         <xsp:content>
>           <xsl:apply-templates/>
>         </xsp:content>
>       </xsp:logic>
> ------------------------------------------
>
> And the code will be a little bit clearer (at least, you can see
> variable scope - so you know where this variable may be used) - of
> course, this is objective.

no. some variables declared in an xsp:logic element may be used in
expressions which are used outside of the xsp:logic element. if you want
your variables to lose scope after your xsp:logic element ends, put curly
braces inside your xsp:logic element (<xsp:logic>{ ... }</xsp:logic>).

> > They rely on the ability to create variables which continue after the
> > xsp:logic tag ends - one of the few technical advantages which
> > XSP has over plain Java.
>
> But now, if your tag declares variable - you can not use this tag again in
> same jsp - or you must do some sort of variable name generation.

that's why well-behaved logicsheets, e.g. esql, mail, smtp, put a prefix
(_esql_) on variables they declare. yeah, i can see some rationale for an
xsp:variable element so that this process is automatic, but others have
disagreed so far.

- donald