[Fontconfig] Is this configuration mean to not work?

[Funda Wang]

Hello,

I would like to write a configuration rules that could replace certain
sizes of certain fonts with another fonts. Why does following rules
won't work? And, could you give me some advice?

<match target="pattern">
	<test name="family" qual="any">
		<string>AR PL ShanHeiSun Uni</string>
	</test>
	<test compare="more_eq" name="size" >
		<double>9</double>
	</test>
	<test compare="less_eq" name="size" >
		<double>12</double>
	</test>
	<edit name="family" mode="assign" binding="strong">
		<string>WenQuanYi Bitmap Song</string>
	</edit>
</match>

Regards.