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From: Justin Mclean <justin@classsoftware.com>
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Subject: try/catch vs in
Date: Fri, 3 Jan 2014 12:26:11 +1100
Message-Id: <B73A2BFC-4245-46DB-A951-67CD76563D91@classsoftware.com>
To: dev@flex.apache.org
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Hi,

While looking at some data grid code I noticed this:

            try
            {
                data =3D data[dataField];
            }
            catch(e:Error)
            {
                data =3D null;
            }

And I was curious to why try catch is used rather than this:

            if (dataField in data)
            {
                data =3D data[dataField];
            }
            else
            {
                data =3D null;
            }

I know "in" can be expensive but so is try catch. I've run each though =
scout and it looks like the in operator is orders of magnitude faster =
and caused no garbage collection both when the field exists and when it =
doesn't. Anyone have any insight/something to add?

Thanks,
Justin=