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For 2021 - online Python 3 training - see ((here)).

Our plans were to retire in summer 2020 and see the world, but Coronavirus has lead us into a lot of lockdown programming in Python 3 and PHP 7.
We can now offer tailored online training - small groups, real tutors - works really well for groups of 4 to 14 delegates. Anywhere in the world; course language English.

Please ask about private 'maintenance' training for Python 2, Tcl, Perl, PHP, Lua, etc.
Dot or Colon separator between table name and member in Lua - what is the difference?

When do I use a dot and when do I use a colon in referencing a table member in Lua? It's a good question and one that we answer (and demonstrate to help make clear) on our Lua Programming Course.

Dot refers to a table member. So if I write
  source.read()
I am saying "run the read function in the table called source". Perhaps that's all I want to do, but it's more likely that the read funiction needs to refer to other things in that same table, so it needs to be passed in as a parameter - so
  source.read(source)
and that works perfectly well. But it looks clumsy, and it means the table name has to be entered twice into the code. So that can be rewritten as
  source:read()

Coded example [here]. Lua course run by us here.
(written 2014-05-06)

 
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
U107 - Object Orientation - the Lua way
  [1692] Towards Object Oriented Programming in Lua - (2008-06-30)
  [1699] If you are learning Lua, here are some more examples - (2008-07-06)
  [1743] First class functions in Lua lead to powerful OO facilities - (2008-08-07)
  [1819] Calling base class constructors - (2008-10-03)
  [2318] For Lua Programmers AND for Town Planners - (2009-08-02)
  [2359] A fresh example - objects the Lua way - (2009-08-13)
  [2455] Lua examples - coroutines, error handling, objects, etc - (2009-10-15)
  [2701] Is Lua an Object Oriented language? - (2010-04-01)
  [2703] Lua Metatables - (2010-04-02)
  [2710] __index and __newindex in Lua - metatable methods - (2010-04-05)
  [3142] Private and Public - and things between - (2011-01-22)
  [3396] Tables as Objects in Lua - a gentle introduction to data driven programming - (2011-08-17)
  [3524] Metaclasses (Python) and Metatables (Lua) - (2011-11-17)
  [3683] Weak references in Lua - what are they, and why use them? - (2012-04-04)
  [3694] Special __ methods you can use in Lua metatables - (2012-04-12)
  [3727] Using Lua tables as objects - (2012-05-11)
  [3730] What is a metatable? How do I set one up? How do I use them? Lua - (2012-05-12)
  [4117] Is Lua an Object Oriented language? - (2013-06-15)
  [4248] Metatables, Metamethods, classes and objects in Lua - (2014-03-18)
  [4572] Tables with values and code in Lua - looks like an object? - (2015-11-05)
  [4573] Classic style OO code - in Lua - (2015-11-05)
  [4753] Lua, Tcl, Python, C and C++ courses - at our Melksham HQ or on your site - forward from July 2017 - (2017-07-02)

U105 - Lua - Tables and the table library.
  [1697] Sorting in lua - specifying your own sort routine - (2008-07-05)
  [1742] Lua - Table elements v table as a whole - (2008-08-07)
  [2346] The indexed and hashed parts of a Lua table - (2009-08-10)
  [2499] ourdog is Greyhound, Staffie and Ginger Cake - (2009-11-09)
  [2699] Lua tables - they are everything - (2010-03-30)
  [3725] Lua Tables - (2012-05-10)
  [4571] Lua - using modules to add your own utilities - (2015-11-04)


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Sending a message to the server and changing text on a page when a button is pressed
Swindon to Weymouth - by train, the traditional way - 2014
Eurpoean Elections, and other elections ahead. Some thoughts on campaigns and policies
String formatting in Lua - string.format as a wrapper for sprintf
Dot or Colon separator between table name and member in Lua - what is the difference?
Lazy operators in Lua - what they mean, and examples
Line, block and nested comments - Lua compared to other languages
Embedding Lua to perform tailored code at an interval
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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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