I've put a lot of thought into it, and have come to the conclusion
that we don't need attributes.
The idea behind "attributes" is this: We combine all of the scopes
into one so we don't have to specify the scope a variable originated
from. But that's no big deal, because Cold Fusion does that anyway.
If you leave out the scope, CF checks all of the following scopes in
the specified order:
1. Local variables created using CFSET and CFQUERY
2. CGI variables
3. File variables
4. URL variables
5. Form variables
6. Cookie variables
7. Client variables
The only problem I see with this is if you want to use fusebox as a
custom tag, you can only access the parameters passed through the
attributes scope. The designers of Fusebox decided to tackle this
problem by putting *everything* in the attributes scope, whether
the circuit is being called as a custom tag or not.
It seems to me that it would be easier to go the opposite direction,
by copying all attributes scoped variables to locally scoped
variables. But then you run into encapsulation problems. Local
variables in the calling template aren't available to custom tags,
but URL & FORM variables are. Still not a major problem because
FORM and URL variables will never override a variable scoped
locally within a custom tag.
The only problem is if I want to check for the existence of a
local variable. The variable may be present in the form scope, but
not the local scope, causing my isDefined("") function returns true
where I expect it to be false. The same problem happens with CFPARAM.
However, I've done some reasearch and found a workaround for that.
Cold Fusion has a default scope for local variables (called "Variables")
and that's the first scope in the list that it checks. So if I
write <cfset x = 1>, CF interprets that as <cfset varibables.x = 1>.
And I can verify that a variable exists in the local scope by
checking 'variables.x' instead of just 'x'.
In order to make this work properly, we would need to make sure all of
our FROM, URL, and ATTRIBUTES variables are copied to the "variables"
scope (CF_FormURL2Variables?), but we could leave off the scope when
referring to our variables, except when we are checking for their
existence.
Patrick
Patrick
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Structure your ColdFusion code with Fusebox. Get the official book at
http://www.fusionauthority.com/bkinfo.cfm
Archives: http://www.mail-archive.com/[email protected]/
Unsubscribe: http://www.houseoffusion.com/index.cfm?sidebar=lists
