Get last part and rest of string

This function has a bug, if it is fed an empty input string it goes into an infinite loop.

Author: Afrow UK (talk, contrib)

Description

This function returns the last part of a string after a certain character and the rest of the string before that character. If the character is not found within the string, then the function returns two empty strings.

Usage

Push " " ; divider char
Push "hello my" ; input string
 Call GetLastPart
Pop $R1 ; last part "my"
Pop $R0 ; first part "hello"

The Function

Function GetLastPart
Exch $R0 ; input
Exch
Exch $R1 ; character
Push $R2
Push $R3
Push $R4
 
 StrCpy $R2 -1
 StrLen $R4 $R0
 Loop:
  IntOp $R2 $R2 + 1
  StrCpy $R3 $R0 1 $R2
  StrCmp $R3 $R1 Chop
  StrCmp $R2 $R4 0 Loop
   StrCpy $R0 ""
   StrCpy $R1 ""
   Goto Done
 Chop:
  StrCpy $R1 $R0 -$R2
  IntOp $R2 $R2 - 1
  StrCpy $R0 $R0 "" -$R2
 Done:
 
Pop $R4
Pop $R3
Pop $R2
Exch $R1 ; before
Exch
Exch $R0 ; after
FunctionEnd