Thanks. I'm actually after the structvalue if it exists and a zero length string if it doesn't. It looks like Rex has me sorted though. Thanks Dom.
On Wed, Sep 8, 2010 at 3:24 AM, Dominic Watson < [email protected]> wrote: > > On a side note, if you're after an output of 'yes' or 'no', this may be > cleaner: > > #YesNoFormat( StructKeyExists(x.classAssign, "#y#head") )# > > Dominic > > > On 8 September 2010 02:30, Michael Grant <[email protected]> wrote: > > > > So I went back and read the docs for IIF. I haven't looked at them in > years > > and I'm shocked that I've used it for SOOOOO many years without really > > knowing exactly how it worked. I would've first read about IIF pre > version > > 5. I can't even find the docs for it. Version 5's description is a little > > vague. You learn something new every day I guess. That's awesome. Thanks > > again Rex. > > > > > > On Tue, Sep 7, 2010 at 8:49 PM, Michael Grant <[email protected]> wrote: > > > >> Wow. I had no idea you could wrap DE in Evaluate. Did you come figure > this > >> out through trial and error or have I just never read it? > >> > >> Thanks for the post rex. > >> > >> > >> On Tue, Sep 7, 2010 at 8:34 PM, rex <[email protected]> wrote: > >> > >>> > >>> A lot of people get DE() wrong. > >>> > >>> IIF does not short-circuit > >>> (http://en.wikipedia.org/wiki/Short-circuit_evaluation), meaning that > >>> your DE() gets evaluated even if the condition is FALSE. So, this will > >>> break: > >>> #iif(false, notFalse, false)# > >>> since notFalse does not exist. Same here: > >>> #iif(true, true, fols)# > >>> since fols does not exist. And finally your code: > >>> #iif(false, DE(x.classAssign["#y#head"]), DE(''))# > >>> breaks since x.classAssign["NAMEhead"] does not exist. > >>> > >>> DE evaluates a STRING parameter and finds double-quotes. If you pass > in > >>> a variable, it looks for the value of that variable. Since you are > >>> passing x.classAssign["#y#head"], it looks for > x.classAssign["NAMEhead"] > >>> and breaks. > >>> > >>> This will work: evaluate(DE("x.classAssign['#y#head']")) - notice the > >>> single-quotes surrounding #y#head! This is because we don't want DE to > >>> escape this, so we don't want to wrap it around double-quotes! > >>> > >>> Here is the code (I used "no value" instead of "", but it's still the > >>> same code that you use): > >>> > >>> <cfset x.classAssign = { > >>> NameHead = "this head", > >>> NoNameHead = "that head" > >>> } /> > >>> <cfoutput> > >>> <cfset y = "Name" /> > >>> #iif(StructKeyExists(x.classAssign,"#y#head"), > >>> evaluate(DE("x.classAssign['#y#head']")), DE("no value"))#<hr /> > >>> <cfset y = "NoExist" /> > >>> #iif(StructKeyExists(x.classAssign,"#y#head"), > >>> evaluate(DE("x.classAssign['#y#head']")), DE("no value"))#<hr /> > >>> > >>> <cfset Y = 'Any' /> > >>> See how these two differ: <br /> > >>> #DE("x.classAssign['#y#head']")#<br /> > >>> #DE('x.classAssign["#y#head"]')# > >>> </cfoutput> > >>> > >>> Michael Grant wrote: > >>> > HA! So I'm not the only one! > >>> > So I thought DE meant "Delay Evaluation" as in "Don't evaluate what's > in > >>> > these little brackets this until you've satisfied the IIF condition." > >>> > > >>> > > >>> > >>> > > > > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Order the Adobe Coldfusion Anthology now! http://www.amazon.com/Adobe-Coldfusion-Anthology-Michael-Dinowitz/dp/1430272155/?tag=houseoffusion Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:336894 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
