My mind was warped very early in college by a love affair with APL. Once you can use it, almost anything else seems normal. Most regular expressions are not that difficult, just a matter of learning a new syntax. But I will say that using "assertions" can be a bit difficult, at least to me. Regular Expressions at a bit like SQL queries to me. The simple ones are easy to understand and learn. But the complicated ones can bend your mind around until you're biting yourself in the rump. One that always makes me sweat is matching the contents inside ' marks, where a single ' is encoded as two ' marks next to each other within the outer ' marks. The same matching contents within parentheses where subparameters within parentheses are permitted. E.g. 'This isn''t quite right!' or (a,b,(c,d),e). Especially difficult is generating a good error message if the person messes up.
I think this is a fairly decent tutorial site for them: http://www.regular-expressions.info/ On Fri, Jul 5, 2013 at 8:53 AM, John Gilmore <[email protected]> wrote: > The intellectual difficulty of learning to use regular expressions is > being greatly exaggerated here. The principles involved could be > written out, for the convenience of notionally reactionary > mainframers, in some few eighty-column card images. > > John Gilmore, Ashland, MA 01721 - USA > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN -- This is a test of the Emergency Broadcast System. If this had been an actual emergency, do you really think we'd stick around to tell you? Maranatha! <>< John McKown ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
