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:336893 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/groups/cf-talk/unsubscribe.cfm
