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Match Tool 2.1

Match Tool 3.0


DEELX Basic Pattern Syntax: Backward Reference

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Backward Reference \nnn

Refer to what a certain group captured. The text at current position must be the same as what a certain group captured.


Backward reference format supported by DEELX:




Backward refer to the group with that number


Backward refer to named group



If the referred group has not captured, the backward reference will match fail.

DEELX uses 3 digital characters at most in backward reference. If you want to express '\1' and a common character '2', you should use '\0012'. If you use '\12' in your pattern in DEELX, it means backward refer to the 12th group.

DEELX will NOT regard \nnn as an octal number,  refer to Simple escaped characters for more details. © 2005 - All Rights Reserved