Home Accessibility Courses Twitter The Mouth Facebook Resources Site Map About Us Contact
 
20.9.2014 - We have just updated our course layouts and descriptions and added our 2015 schedule.

Ruby v Perl - interpollating variables

When printing in Perl, you can drop a variable into a double quoted string ant it will be interpretter for you:

"--- $number ---"

If you want to perform an operation on the variable, though, it's not as easy - you have to come out of the double quoted string, do the calculation, then start another string:

"--- ",$number + 1," ---"

In Ruby, variable names do NOT start with a $ so you can't simply drop them in to your double quoted string. Instead, you can write #{expression} within the double quotes and that gives you ...

"--- #{number + 1} ---"

And that's fabulous - it gives you the ability to write any expresion you want, or just a simple variable, with a double quoted string and have the same simple syntax for both.
(written 2006-12-15, updated 2006-12-21)

 
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
P205 - Perl - Initial String Handling
  [3770] Sample answers to training course exercises - available on our web site - (2012-06-21)
  [3548] Dark mornings, dog update, and Python and Lua courses before Christmas - (2011-12-10)
  [3547] Using Perl to generate multiple reports from a HUGE file, efficiently - (2011-12-09)
  [3411] Single and double quotes strings in Perl - what is the difference? - (2011-08-30)
  [3005] Lots of ways of doing it in Perl - printing out answers - (2010-10-19)
  [2963] Removing the new line with chop or chomp in Perl - what is the difference? - (2010-09-21)
  [2832] Are you learning Perl? Some more examples for you! - (2010-06-27)
  [2816] Intelligent Matching in Perl - (2010-06-18)
  [2798] Perl - skip the classics and use regular expressions - (2010-06-08)
  [1860] Seven new intermediate Perl examples - (2008-10-30)
  [1849] String matching in Perl with Regular Expressions - (2008-10-20)
  [1608] Underlining in Perl and Python - the x and * operator in use - (2008-04-12)
  [1195] Regular Express Primer - (2007-05-20)
  [970] String duplication - x in Perl, * in Python and Ruby - (2006-12-07)
  [324] The backtick operator in Python and Perl - (2005-05-25)
  [254] x operator in Perl - (2005-03-22)
  [31] Here documents - (2004-08-28)

R109 - Ruby - Strings and Regular Expressions
  [3758] Ruby - standard operators are overloaded. Perl - they are not - (2012-06-09)
  [3757] Ruby - a teaching example showing many of the language features in short but useful program - (2012-06-09)
  [3621] Matching regular expressions, and substitutions, in Ruby - (2012-02-23)
  [3424] Divide 10000 by 17. Do you get 588.235294117647, 588.24 or 588? - Ruby and PHP - (2011-09-08)
  [2980] Ruby - examples of regular expressions, inheritance and polymorphism - (2010-10-02)
  [2623] Object Oriented Ruby - new examples - (2010-02-03)
  [2621] Ruby collections and strings - some new examples - (2010-02-03)
  [2614] Neatly formatting results into a table - (2010-02-01)
  [2608] Search and replace in Ruby - Ruby Regular Expressions - (2010-01-31)
  [2295] The dog is not in trouble - (2009-07-17)
  [2293] Regular Expressions in Ruby - (2009-07-16)
  [1891] Ruby to access web services - (2008-11-16)
  [1887] Ruby Programming Course - Saturday and Sunday - (2008-11-16)
  [1875] What are exceptions - Python based answer - (2008-11-08)
  [1588] String interpretation in Ruby - (2008-03-21)
  [1305] Regular expressions made easy - building from components - (2007-08-16)
  [986] puts - opposite of chomp in Ruby - (2006-12-15)


Back to
puts - opposite of chomp in Ruby
Previous and next
or
Horse's mouth home
Forward to
You should think you're first in a hotel room
Some other Articles
Adding a member to a Hash in Ruby
Ruby - Totally Topical
Melksham Quiz
You should think you're first in a hotel room
Ruby v Perl - interpollating variables
Equality in Ruby - == eql? and equal?
Cardinal numbers and magic numbers
Blessing in Perl / Member variable in Ruby
Notes from the white board
4291 posts, page by page
Link to page ... 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86 at 50 posts per page


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.

Link to Ezine home page (for reading).
Link to Blogging home page (to add comments).

You can Add a comment or ranking to this page

© WELL HOUSE CONSULTANTS LTD., 2014: Well House Manor • 48 Spa Road • Melksham, Wiltshire • United Kingdom • SN12 7NY
PH: 01144 1225 708225 • FAX: 01144 1225 899360 • EMAIL: info@wellho.net • WEB: http://www.wellho.net • SKYPE: wellho

PAGE: http://www.wellho.net/mouth/987_Ruby ... ables.html • PAGE BUILT: Thu Sep 18 15:30:25 2014 • BUILD SYSTEM: WomanWithCat