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Python and Tcl - public course schedule [here]
Private courses on your site - see [here]
Please ask about maintenance training for Perl, PHP, Lua, etc
 
Do not copy and paste code - there are much better ways

If you find yourself using copy and paste to duplicate a piece of code, take a step back and think again. You're doubling your maintenance work, with two separate sets of code to look after and keep in step from that day forwards.

Are you going to give me the "but I have to change one copy a bit" excuse? Please don't ... in identifying which bits need changing, you have identified the parameters for a named block of code ... which will be known as a sub / subroutine / function / macro / method / procedure / command depending on which language you're writing in.

There's an example in [this bit of code] which I wrote yesterday in Perl, looking for Christmas topics within place names (Well - as someone else said ... "the programs on the TV weren't worth watching") ...

And if you want to try the code out, there's a web based derivative [here]. Enjoy!

(written 2009-12-26, updated 2010-01-06)

 
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
P204 - Perl - Conditionals and Loops
  [4323] Learning to program - Loop statements such as while - (2014-11-22)
  [4322] Learning to Program - the conditional statement (if) - (2014-11-21)
  [4031] Showing what programming errors look like - web site pitfall - (2013-03-06)
  [3895] Flowchart to program - learning to program with Well House - (2012-10-14)
  [3397] Does a for loop evaluate its end condition once, or on every iteration? - (2011-08-18)
  [3004] Increment operators for counting - Perl, PHP, C and others - (2010-10-18)
  [2832] Are you learning Perl? Some more examples for you! - (2010-06-27)
  [2711] For loop - checked once, or evety time? Ruby v Perl comparison and contrast - (2010-04-07)
  [2351] Ternary operators alternatives - Perl and Lua lazy operators - (2009-08-12)
  [1727] Equality and looks like tests - Perl - (2008-07-29)
  [1696] Saying NOT in Perl, PHP, Python, Lua ... - (2008-07-04)
  [1607] Learning to program in Perl - (2008-04-11)
  [1477] Decisions - small ones, or big ones? - (2007-12-18)
  [1468] Lexical v Arithemetic testing, Bash and Perl - (2007-12-11)
  [1191] Smart English Output - via PHP and Perl ? : operator - (2007-05-18)
  [930] -> , >= and => in Perl - (2006-11-18)
  [353] Wimbledon Neck - (2005-06-20)

P209 - Subroutines in Perl
  [3833] Learning to use existing classes in Perl - (2012-08-10)
  [3574] Perl functions such as chop change their input parameters - (2012-01-10)
  [3066] Separating groups of variables into namespaces - (2010-11-24)
  [2929] Passing a variable number of parameters in to a function / method - (2010-08-20)
  [2833] Fresh Perl Teaching Examples - part 2 of 3 - (2010-06-27)
  [2069] Efficient calls to subs in Perl - avoid duplication, gain speed - (2009-03-07)
  [1921] Romeo and Julie - (2008-12-04)
  [1860] Seven new intermediate Perl examples - (2008-10-30)
  [1850] Daisy the Cow and a Pint of Ginger Beer - (2008-10-21)
  [1826] Perl - Subs, Chop v Chomp, => v , - (2008-10-08)
  [1784] Global - Tcl, PHP, Python - (2008-09-03)
  [1782] Calling procs in Tcl and how it compares to Perl - (2008-09-02)
  [1202] Returning multiple values from a function (Perl, PHP, Python) - (2007-05-24)
  [1163] A better alternative to cutting and pasting code - (2007-04-26)
  [969] Perl - $_ and @_ - (2006-12-07)
  [775] Do not duplicate your code - (2006-06-23)
  [588] Changing @INC - where Perl loads its modules - (2006-02-02)
  [531] Packages in packages in Perl - (2005-12-16)
  [357] Where do Perl modules load from - (2005-06-24)
  [308] Call by name v call by value - (2005-05-11)
  [96] Variable Scope - (2004-10-22)

Q101 - Object Orientation and General technical topics - Programming Principles
  [4645] What are callbacks? Why use them? An example in Python - (2016-02-11)
  [4632] Remember to ask the question before you listen for the answer - (2016-01-26)
  [4611] Hungarian, Camel, Snake and Kebab - variable naming conventions - (2016-01-03)
  [4325] Learning to program - what are algorithms and design patterns? - (2014-11-22)
  [4206] Writing the perfect program in Tcl? - (2013-11-13)
  [4153] Rooms available tonight - how to code an algorithm from first principles - (2013-08-19)
  [4118] We not only teach PHP and Python - we teach good PHP and Python Practice! - (2013-06-18)
  [4090] Test Driven Development in Python - Customer Comes First - (2013-05-16)
  [4061] Seamless, integrated IT - we have a long way to go! - (2013-04-11)
  [4003] Web and console - same principle, same code - Ruby example - (2013-02-14)
  [3954] Lesson 1 in programing - write clean, reuseable and maintainable tidy code - (2012-12-16)
  [3928] Storing your intermediate data - what format should you you choose? - (2012-11-20)
  [3878] From Structured to Object Oriented Programming. - (2012-10-02)
  [3673] Object oriented or structured - a comparison in Python. Also writing clean regular expressions - (2012-03-26)
  [3551] Some terms used in programming (Biased towards Python) - (2011-12-12)
  [3548] Dark mornings, dog update, and Python and Lua courses before Christmas - (2011-12-10)
  [3542] What order are operations performed in, in a Perl expression? - (2011-12-07)
  [3456] Stepping stones - early coding, and writing re-usable code quickly - (2011-09-24)
  [3026] Coding efficiency - do not repeat yourself! - (2010-11-02)
  [2964] An introduction to file handling in programs - buffering, standard in and out, and file handles - (2010-09-21)
  [2915] Looking up a value by key - associative arrays / Hashes / Dictionaries - (2010-08-11)
  [2878] Program for reliability and efficiency - do not duplicate, but rather share and re-use - (2010-07-19)
  [2769] Easy - but for whom? - (2010-05-18)
  [2737] Improving your function calls (APIs) - General and PHP - (2010-04-24)
  [2586] And and Or illustrated by locks - (2010-01-17)
  [2510] The music of the stock market - (2009-11-22)
  [2415] Variable names like i and j - why? - (2009-09-22)
  [2327] Planning! - (2009-08-08)
  [2310] Learning to write high quality code in Lua - (2009-07-30)
  [2228] Where do I start when writing a program? - (2009-06-11)
  [2022] Pre and post increment - the ++ operator - (2009-02-03)
  [2001] I have not programmed before, and need to learn - (2009-01-19)


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Perl and the Common Gateway Interface - out of fashion but still very useful?
Some other Articles
Adding retrospective ALT attributes to IMG
On a short walk from home
Web site traffic - real users, or just noise?
Perl and the Common Gateway Interface - out of fashion but still very useful?
Do not copy and paste code - there are much better ways
Christmas Day ...
Ten years ago, we moved to Melksham Spa
The great thing about snow ....
How well do you know Melksham - a quiz for Christmas
Scraping content for your own page via PHP
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This is a page archived from The Horse's Mouth at http://www.wellho.net/horse/ - the diary and writings of Graham Ellis. Every attempt was made to provide current information at the time the page was written, but things do move forward in our business - new software releases, price changes, new techniques. Please check back via our main site for current courses, prices, versions, etc - any mention of a price in "The Horse's Mouth" cannot be taken as an offer to supply at that price.

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