= !MapGuide RFC 50 - Enhance expression engine concat function =

This page contains a change request (RFC) for the !MapGuide Open Source project.  
More !MapGuide RFCs can be found on the [wiki:MapGuideRfcs RFCs] page.


== Status == 
 
||RFC Template Version||(1.0)|| 
||Submission Date|| June 25, 2008 ||
||Last Modified|| Bruce Dechant [[Timestamp]]||
||Author||Bruce Dechant||
||RFC Status||draft|| 
||Implementation Status||draft||
||Proposed Milestone||2.1||
||Assigned PSC guide(s)||Bruce Dechant||
||'''Voting History'''|| ||
||+1|| ||
||+0|| ||
||-0|| ||
||-1|| ||
 
== Overview ==

This RFC is for adding an additional syntax to the concat function of the expression engine.

== Motivation ==

The existing concat function syntax is difficult to work with when multiple concatenations need to be done. It requires the concat functions be nested whenever a new item needs to be concatenated.

== Proposed Solution ==

The proposed solution is to add support for an additional syntax to the concat function.

Old syntax:
{{{
concat('Parcel ID: ', concat( PID , concat('\nOwner Name: ', concat(NullValue (  OWNER_NAME , '' ) , concat('\nAddress: ',  SITE_ADDR )))))

}}}

New syntax:
{{{
concat('Parcel ID: ', PID , '\nOwner Name: ', NullValue (  OWNER_NAME , '' ) , '\nAddress: ', SITE_ADDR )

}}}

The new syntax will consist of a comma delimited list of concatenation items.

== Implications ==

The existing concat function syntax will continue to be supported in addition to the new syntax.

== Test Plan ==

Test that the existing and new concat function syntax work.

== Funding/Resources ==

None at this time.