Constants in Ruby

2a7f Constants in Ruby

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Constants in Ruby

If you want to have a read only variable in Ruby, start its name with a capital letter (and you may like to go with a convention of using capitals right through the variable name).

Note that a Ruby constant - a name starting with a capital - hasa global scope, just like a variable name that starts with a $

There's an example [here] from today's Learning to Program in Ruby Training Course.

(written 2010-02-01)

Associated topics are indexed under

R103 - Basic Ruby Language Elements
  [3917] BODMAS - the order a computer evaluates arithmetic expressions - (2012-11-09)
  [3758] Ruby - standard operators are overloaded. Perl - they are not - (2012-06-09)
  [3430] Sigils - the characters on the start of variable names in Perl, Ruby and Fortran - (2011-09-10)
  [3278] Do I need to initialise variables - programming in C, C++, Perl, PHP, Python, Ruby or Java. - (2011-05-05)
  [2617] Comparing floating point numbers - a word of caution and a solution - (2010-02-01)
  [2296] Variable scope - what is it, and how does it Ruby? - (2009-07-18)
  [2287] Learning to program in Ruby - examples of the programming basics - (2009-07-15)
  [986] puts - opposite of chomp in Ruby - (2006-12-15)

R110 - Ruby - Special Variables and Pseudo-Variables
  [3757] Ruby - a teaching example showing many of the language features in short but useful program - (2012-06-09)
  [2623] Object Oriented Ruby - new examples - (2010-02-03)
  [1891] Ruby to access web services - (2008-11-16)
  [1587] Some Ruby programming examples from our course - (2008-03-21)
  [1586] Variable types in Ruby - (2008-03-21)
  [990] Ruby - Totally Topical - (2006-12-16)

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Defining a static method - Java, Python and Ruby
String to number conversion with error trapping in Ruby
Neatly formatting results into a table
Constants in Ruby
The Model, View, Controller architecture (MVC) - what, why and how.
Sunday Evening, City of London
Cheat Sheet - what do you need for Ruby on Rails?
Scope of variables - important to Ruby on Rails
Search and replace in Ruby - Ruby Regular Expressions

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