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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Hi Vincent and Jonathan,<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>I can’t tell who said what here due to the way your
editors formatted the text. I thought about a possible solution to the performance
problems I mentioned, but I don’t think it will be viable. I thought
about always caching the results of the lookup, so object interfaces would only
need to be checked the first time a type was used in a template. Unfortunately,
due to the way templates inherit attribute renderers, several problems emerge:<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><span
style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Caching the renderers would result in a copy of all
type->renderer maps in every template, incurring both a space and time overhead.<o:p></o:p></span></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><span
style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Caching the renderers would break the attribute renderer
inheritance scheme.<o:p></o:p></span></p>
<p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span
style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><span
style='mso-list:Ignore'>3.<span style='font:7.0pt "Times New Roman"'>
</span></span></span><![endif]><i><span style='font-size:11.0pt;font-family:
"Calibri","sans-serif";color:#1F497D'>Not</span></i><span style='font-size:
11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'> caching the renderers
would mean checking all interface base types and interfaces while walking up
the template inheritance chain. This would be a more substantial hit than
GetAttribute, likely more than doubling the time required to render templates. I’ll
profile this to make sure, but if my analysis proves correct the feature will
have to be completely reengineered before we could talk about incorporating it
into the library.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Sam<o:p></o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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