Building Structs will probably always perform faster than lists for this type of thing, as Strings are immutable, and therefore have to be recreated every time you change them.
Mark On Thu, Nov 27, 2008 at 7:29 AM, Brian Dumbledore <[EMAIL PROTECTED]> wrote: > I didn't want to extend the years old discussion on this thread, > http://www.houseoffusion.com/groups/cf-talk/thread.cfm/threadid:19468 > > I was looking for a custom tag which given two lists list1,list2 will give me > back a struct with two lists 'toadd' and 'todelete'. > > toadd -- elements from list2 to be added to list1 > todelete -- elements from list1 to be deleted (those that are not present in > list2) > > I wrote two versions, one based on lists and the other based on struct, in > all cases (even smaller sizes), struct version outperforms list version. > > Anyone care to comment? Both versions given below: > > STRUCT VERSION: > <!--- usage > <cf_listcompare list1="#list1#" list2="#list2#" returnvariable="abc" > delimiter=","> > ---> > <cfparam name="attributes.list1" default="" type="string"> > <cfparam name="attributes.list2" default="" type="string"> > <cfparam name="attributes.delimiter" default=","> > <cfparam name="attributes.returnvariable" type="variablename" > default="result"> > <cfset caller[attributes.returnvariable]=structnew()> > <cfset struct1 = structnew()> > <cfset struct2 = structnew()> > <cfloop list="#attributes.list1#" index="idx" > delimiters="#attributes.delimiter#"> > <cfset structinsert(struct1,"#idx#","","yes")> > </cfloop> > <cfset list1=structkeylist(struct1,"#attributes.delimiter#")> > > <cfloop list="#attributes.list2#" index="idx" > delimiters="#attributes.delimiter#"> > <cfset structinsert(struct2,"#idx#","","yes")> > </cfloop> > <cfset list2=structkeylist(struct2,"#attributes.delimiter#")> > > <cfif attributes.list1 neq "" or attributes.list2 neq ""> > <cfset toadd = structnew()> > <cfset todelete = structnew()> > <cfloop list="#list2#" index="idx" delimiters="#attributes.delimiter#"> > <cfif not structkeyexists(struct1,"#idx#")> > <cfset structinsert(toadd,"#idx#","")> > </cfif> > </cfloop> > <cfloop list="#list1#" index="idx" delimiters="#attributes.delimiter#"> > <cfif not structkeyexists(struct2,"#idx#")> > <cfset structinsert(todelete,"#idx#","")> > </cfif> > </cfloop> > <cfset > structinsert(caller[attributes.returnvariable],"toadd","#structkeylist(toadd,attributes.delimiter)#")> > <cfset > structinsert(caller[attributes.returnvariable],"todelete","#structkeylist(todelete,attributes.delimiter)#")> > </cfif> > > LIST VERSION: > > <cfparam name="attributes.list1" default="" type="string"> > <cfparam name="attributes.list2" default="" type="string"> > <cfparam name="attributes.delimiter" default=","> > <cfparam name="attributes.returnvariable" type="variablename" > default="result"> > <cfset caller[attributes.returnvariable]=structnew()> > <cfif attributes.list1 neq "" or attributes.list2 neq ""> > <cfset toadd = ""> > <cfset todelete = ""> > <cfloop list="#attributes.list2#" index="idx" > delimiters="#attributes.delimiter#"> > <cfif not > listfind(attributes.list1,idx,"#attributes.delimiter#") and not > listfind(toadd,idx,"#attributes.delimiter#")> > <cfset toadd = > listappend(toadd,idx,"#attributes.delimiter#")> > </cfif> > </cfloop> > <cfloop list="#attributes.list1#" index="idx" > delimiters="#attributes.delimiter#"> > <cfif not > listfind(attributes.list2,idx,"#attributes.delimiter#") and not > listfind(todelete,idx,"#attributes.delimiter#")> > <cfset todelete = > listappend(todelete,idx,"#attributes.delimiter#")> > </cfif> > </cfloop> > <cfset > structinsert(caller[attributes.returnvariable],"toadd","#toadd#")> > <cfset > structinsert(caller[attributes.returnvariable],"todelete","#todelete#")> > </cfif> > > > > > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Adobe® ColdFusion® 8 software 8 is the most important and dramatic release to date Get the Free Trial http://ad.doubleclick.net/clk;207172674;29440083;f Archive: http://www.houseoffusion.com/groups/cf-talk/message.cfm/messageid:315998 Subscription: http://www.houseoffusion.com/groups/cf-talk/subscribe.cfm Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4
