This is really just some rough notes but is a starting point to something more...
|Regular Expression||What it does|
||Matches lines starting “Line23:”, it looks for the word line at the start of the line and then any number of digits followed by a colon|
||Match lines starting “Found” and then having any number of any characters after that to the end of the line|
||Match a “” and then also match the closing “>”. This has the effect of removing all xml tags, opening and closing.|
||Searches for an upper or lower case letter in round brackets ( ) or square brackets [ ]|
||Match any number of characters followed by a tab|
||Match the start of the line, then any number of any character up to and including a tab|
Being a Python fan, then it is always one of my first choices, for Regular Expression information then see Regular Expression HOWTO — Python v3.3.3 documentation or the 2.x equivalent if that is your version.
It is worth noting that Perl based regular expressions are a common standard and one that UltraEdit can use. If you are working with html or xml tags then you will need to understand UltraEdit perl regex tutorial: non-greedy regular expressions, which is a helpful article.
Being a very powerful and flexible editor it will hardly be a surprise that UltraEdit has three different regular expression engines built in: Perl, Unix, UltraEdit. The last two are documented at Regular expressions with find and replace. The Perl ones are described at the following:
Getting started with Perl regex in UltraEdit and UEStudio
Perl regular expressions in UltraEdit and UEStudio: Digging deeper
Perl regex backreferences in Find and Replace in UltraEdit