Redet allows the user to construct regular expressions and test them against
input data by executing any of a variety of search programs, editors, and
programming languages that make use of regular expressions. When a suitable
regular expression has been constructed it may be saved to a file. redet stands
for Regular Expression Development and Execution Tool. For each program, a
palette showing the available regular expression syntax is provided. Selections
from the palette may be copied to the regular expression window with a mouse
click. Users may add their own definitions to the palette via their
initialization file. Redet also keeps a list of the regular expressions
executed, from which entries may be copied back into the regular expression
under construction. The history list is saved to a file and restored on
startup, so it persists across sessions. So long as the underlying program
supports Unicode, redet allows UTF-8 Unicode in both test data and regular
expressions

WWW: http://www.billposer.org/Software/redet.html