Mailing-List: contact dev-help@apr.apache.org; run by ezmlm
Precedence: bulk
Received-SPF: pass (asf.osuosl.org: domain of jorton@redhat.com designates
 66.187.233.31 as permitted sender)
Date: Wed, 17 Aug 2005 07:40:55 +0100
From: Joe Orton <jorton@redhat.com>
To: dev@apr.apache.org
Subject: Re: APR_ARRAY_FOO convenience macros
Message-ID: <20050817064055.GB19961@redhat.com>
Mail-Followup-To: dev@apr.apache.org
References: <43014E5D.9080008@electricjellyfish.net>
 <6.2.1.2.2.20050816014759.071c1e30@pop3.rowe-clan.net>
Mime-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Disposition: inline
In-Reply-To: <6.2.1.2.2.20050816014759.071c1e30@pop3.rowe-clan.net>
User-Agent: Mutt/1.4.2.1i

On Tue, Aug 16, 2005 at 01:49:55AM -0500, William Rowe wrote:
> At 09:24 PM 8/15/2005, Garrett Rooney wrote:
> >So back in Dec 2003 Sander Striker suggested [1] adding Subversion's macros for manipulating apr arrays (APR_ARRAY_IDX, which automates the casting needed to access entries in the array, and APR_ARRAY_PUSH, which automates the casting needed to add entries to the array) to apr_tables.h.  Roy Fielding commented [2] that he felt the macros tied the interface to the implementation too much, and Greg Stein replied [3] that they had to be done as macros, not functions, because of the need to pass a type name for the cast.
> 
> IIUC, these are not typesafe?

APR arrays are fundamentally not type-safe object stores.

In case it's not clear, these are the macros in question:

/** index into an apr_array_header_t */
#define APR_ARRAY_IDX(ary,i,type) (((type *)(ary)->elts)[i])

/** easier array-pushing syntax */
#define APR_ARRAY_PUSH(ary,type) (*((type *)apr_array_push (ary)))

joe