Problem with xlt proc

I’m using a piece of code in a translate to parse a fixed length left justified field and replace a leading ‘A’ (if it exists) with ‘AA’.

>A123456       < should translate to >AA123456      < This fails occasionally although I can’t reproduce it using the test tool. The error I’ve seen is: >232595        < comes out as >        < My code is: ###################################################################### # Name: XltAtoAE # Purpose: Change PAS A number to AA. # # UPoC type: xltp # Args: none # Notes: All data is presented through special variables.  The initial #   upvar in this proc provides access to the required variables. # #  This proc style only works when called from a code fragment #  within an XLT. # # v1  DTH 03/12/03 Initial Version, for PAS to Telepath. # v2  DTH 22/02/05 To change ‘A’ to ‘AA’ proc XltAtoAE {} {  upvar xlateInVals   xlateInVals    xlateOutVals  xlateOutVals  set x [lindex $xlateInVals 0]  switch $x    “”        {}    “default” {regsub “A” $x “AA” y;   set xlateOutVals

}

}

Any suggestions for improvement would be appreciated.

Thanks,

Dave