Can't enter < or > when doing regular expression find and replace

Help & Support
1

When entering a regular expression search string, Directory Opus will not let me enter the characters Open angle bracket (<) or Close angle bracket (>). Attempts to enter these characters is ignored with a warning tone. Neither of these are reserved character in regular expressions. This makes it impossible to enter a positive lookbehind string, (?<=text) or a negative lookbehind string, (?<!text). Am I missing something here, or is this a bug?

2

I am afraid lookbehind is not supported by Opus' Regex engine:

(via https://www.gpsoft.com.au/help/opus12/index.html#!Documents/Regular_Expression_Syntax.htm)

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3

Negative Asserts are supported, on the other hand, and should be able to do the same sort of thing.

4

Ok. Thanks for that. And of course the < and > characters are not valid in file or folder names, and so it makes no sense trying to search for them. I now see why Directory Opus doesn't like these characters being entered in a bulk file/folder rename string. Thanks for the quick response.

5

So DO is written in C++ and uses its RegEx library, right?

Just to be sure, because I'm using RegExBuddy which is capable of switching to various programming languages, and I'm using this tool for testing purposes.

6

Yes, although C++ has lots of regex libraries/modes. (Regex is more an idea than an actual standard.) The exact mode is documented in the manual page which lxp already linked to above.

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