CFML is a tag based language. When tags need arguments or options passed to them, they are passed as attributes. This is an integral part of what makes CFML so easy and so productive. But sometimes, having to pass attributes can be a hindrance. Consider a simple example, a <CFQUERY> where you sometimes just need basic attributes (NAME and DATASOURCE perhaps) but other times want additional optional attributes (like USERNAME and PASSWORD). There is no way to conditionally include attributes in a tag, and so you end up having to write code like this:
<CFIF some condition>
<CFQUERY NAME="myQuery" DATASOURCE="myDSN">
...
</CFQUERY>
<CFELSE>
<CFQUERY NAME="myQuery" DATASOURCE="myDSN"
USERNAME="#SESSION.username#"
PASSWORD="#SESSION.password#">
...
</CFQUERY>
</CFIF>
It's just an example, but it's not pretty at all. And this same is true if you conditionally want to add query caching, or specify an SMTP server in <CFMAIL>, and so on.
Scorpio solves this problem in the simple and elegant fashion we've come to expect from ColdFusion. In Scorpio you can pass all tag attributes as a single structure, an ARGUMENTSCOLLECTION. Here is a simple <CFQUERY>:
<CFSET args=StructNew()>
<CFSET args.name="myQuery">
<CFSET args.datasource="myDSN">
<CFQUERY ARGUMENTSCOLLECTION="#args#">
...
</CFQUERY>
As structure members can be added conditionally, passing optional attributes becomes a simple matter of conditionally adding members, as seen here:
<CFSET args=StructNew()>
<CFSET args.name="myQuery">
<CFSET args.datasource="myDSN">
<CFIF some condition>
<CFSET args.username=SESSION.username>
<CFSET args.password=SESSION.password>
</CFIF>
<CFIF condition that determines that caching is needed>
<CFSET args.cachedwithin=CreateTimeSpan(0,0,0,1,0,0)>
</CFIF>
<CFQUERY ARGUMENTSCOLLECTION="#args#">
...
</CFQUERY>
This new syntax can be used by all sorts of tags, including <CFCONTENT>, <CFFILE>, <CFFTP>, <CFIMAGE>, <CFMAIL>, <CFXML>, and many more.
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