CRiSP Weblog

Regular expressions....who wants them?!

We all do - they can make complex tasks trivial to do, e.g. search and replace, swapping of columns.

Unfortunately they tend to be cryptic and read-only for anything other than the most trivial of things.

CRiSP supports three flavors of regexp - the original BRIEF version, Unix style, and Perl style.

Perl regexps are very powerful - too powerful. Perl 6 is introducing sophisticated parser based regexps which allow you to do things regexps could never do before.

But a one liner becomes a program, with loss of readability.

I am not knocking them - I am jealous, and maybe CRiSP will adopt them too in the fulness of time, but, where a regexp ends, a macro begins.

I have been a fan for many years of virtualisation products, especially VMware. It just works. Until I encountered vmware server 2.0 beta release and I just screamed at how poor a product can be. The early vmware products were a few megabytes of executable, and a functional and easy to use interface. The new server release is 500+MB of junk - a crippled interface running on a browser, loss of functionality, change for changes sake and not to be recommended. I took VirtualBox for a test drive - a free product, and....it just works. I may try Xen again, but it too suffered in the past of difficult to use and setup. Why do companies take very good products and detonate them? Who knows

I haven't blogged for a while, but thought it worth trying to resurrect the idea.

CRiSP is a powerful editor - it has so many features, from the simple to the obscure. Each feature was created with a goal in mind - either a request from someone, or a desire to fix a specific problem.

CRiSP's grep feature where you can select specific lines in a single file or all files, and then filter them down to just the set you require is predicated on the unix command line and pipes - where you can start by using a simple grep, and pipe into another grep to reduce the selection to what you want.

You can activate this in CRiSP by using the "<F10>grep" command and once you are in a popup window, use <Alt-F> to invoke a "Filter:" prompt and start to cull the selection.

A feature so powerful, that many people may not understand it, until you try it.