Over the years I've been teaching people about Regular Expressions, I've learnt what does and doesn't work in such tuition. A casual question I saw yesterday got me writing, and I've just posted up a new technical article to
the solution centre - see
here (it will open in a separate window).
It's amazing - truly amazing - how often there's a code requirement to say "does this look like that" and that's exactly what regular expressions do. In fact, I added an extra markup facility to the solution centre as I was writing the article as I wanted an extra way to emphasise and - guess what - the methodolgy I used was a regular expression!
There are full tables of Regular Expression elements on our web site too - see
here as a starter, and we even
offer regular expression mousemats for sale at, of course, a very reasonable cost!
(written 2007-05-20, updated 2007-05-21)
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
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[1110] Python - two different splits - (2007-03-15)
[1517] Python - formatting objects - (2008-01-24)
[1608] Underlining in Perl and Python - the x and * operator in use - (2008-04-12)
[1876] Python Regular Expressions - (2008-11-08)
[2284] Strings as collections in Python - (2009-07-12)
[2406] Pound Sign in Python Program - (2009-09-15)
[2692] Flexible search and replace in Python - (2010-03-25)
[2721] Regular Expressions in Python - (2010-04-14)
[2765] Running operating system commands from your Python program - (2010-05-14)
[2780] Formatted Printing in Python - (2010-05-25)
[2814] Python - splitting and joining strings - (2010-06-16)
[3090] Matching to a string - what if it matches in many possible ways? - (2010-12-17)
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[3468] Python string formatting - the move from % to str.format - (2011-10-08)
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[3796] Backquote, backtic, str and repr in Python - conversion object to string - (2012-07-05)
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[4027] Collections in Python - list tuple dict and string. - (2013-03-04)
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[4213] Formatting options in Python - (2013-11-16)
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[4360] Python - comparison of old and new string formatters - (2014-12-22)
[4593] Command line parameter handling in Python via the argparse module - (2015-12-08)
[4595] Python formatting update - including named completions - (2015-12-10)
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[1336] Ignore case in Regular Expression - (2007-09-08)
[1410] Tcl / regsub - changing a string and using interesting bits - (2007-10-27)
[1412] Sparse and Greedy matching - Tcl 8.4 - (2007-10-27)
[1613] Regular expression for 6 digits OR 25 digits - (2008-04-16)
[4205] Regular Expression Substitution - Tcl - (2013-11-12)
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[1875] What are exceptions - Python based answer - (2008-11-08)
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[1891] Ruby to access web services - (2008-11-16)
[2293] Regular Expressions in Ruby - (2009-07-16)
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[3758] Ruby - standard operators are overloaded. Perl - they are not - (2012-06-09)
[4388] Global Regular Expression matching in Ruby (using scan) - (2015-01-08)
[4505] Regular Expressions for the petrified - in Ruby - (2015-06-03)
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[1849] String matching in Perl with Regular Expressions - (2008-10-20)
[1860] Seven new intermediate Perl examples - (2008-10-30)
[2798] Perl - skip the classics and use regular expressions - (2010-06-08)
[2816] Intelligent Matching in Perl - (2010-06-18)
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[3411] Single and double quotes strings in Perl - what is the difference? - (2011-08-30)
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[337] the array returned by preg_match_all - (2005-06-06)
[422] PHP Magic Quotes - (2005-08-22)
[493] Running a Perl script within a PHP page - (2005-11-12)
[558] Converting between acres and hectares - (2006-01-08)
[574] PHP - dividing a string up into pieces - (2006-01-23)
[589] Robust PHP user inputs - (2006-02-03)
[608] Don't expose your regular expressions - (2006-02-15)
[642] How similar are two words - (2006-03-11)
[716] Evaluating arithmetic expressions in configuration files - (2006-05-10)
[728] Looking ahead and behind in a Regular Expression - (2006-05-22)
[1008] Date conversion - PHP - (2006-12-26)
[1058] PHP Regular expression to extrtact link and text - (2007-01-31)
[1372] A taster PHP expression ... - (2007-09-30)
[1533] Short and sweet and sticky - PHP form input - (2008-02-06)
[1603] Do not SHOUT and do not whisper - (2008-04-06)
[1799] Regular Expressions in PHP - (2008-09-16)
[2046] Finding variations on a surname - (2009-02-17)
[2165] Making Regular Expressions easy to read and maintain - (2009-05-10)
[2238] Handling nasty characters - Perl, PHP, Python, Tcl, Lua - (2009-06-14)
[2629] Curly braces within double quoted strings in PHP - (2010-02-09)
[3020] Handling (expanding) tabs in PHP - (2010-10-29)
[3515] PHP - moving from ereg to preg for regular expressions - (2011-11-11)
[3516] Regular Expression modifiers in PHP - summary table - (2011-11-12)
[3534] Learning to program in PHP - Regular Expression and Associative Array examples - (2011-12-01)
[3788] Getting more than a yes / no answer from a regular expression pattern match - (2012-06-30)
[3789] More than just matching with a regular expression in PHP - (2012-06-30)
[3790] Solution looking for a problem? Lookahead and Lookbehind - (2012-06-30)
[4071] Setting up strings in PHP - (2013-04-27)
[4072] Splitting the difference with PHP - (2013-04-27)
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