These are some examples I like to use when learning or revisiting a language. If you're interested in comparative implementations like this, please be sure to visit: Rosetta Code, Programming Examples Alike Cookbook, and Literate Programs.

• FizzBuzz -- printing, loops
  • python: FizzBuzz.py
  • ruby: FizzBuzz.rb
  • perl: FizzBuzz.pl
  • javascript: FizzBuzz.html
  • C#: FizzBuzz.cs
  • F#: FizzBuzz.fs
  • PHP: FizzBuzz.php
• QuickSort -- arrays, comparators, unit testing
  • python: quicksort.py
  • ruby: quicksort.rb
  • perl: QuickSort.pm TestQuickSort.pl
  • javascript: QuickSort.js TestQuickSort.jst
  • C#: QuickSort.cs TestQuickSort.cs
  • F# (with NUnit invoked from F#): QuickSort.fs
  • PHP: quicksort.php TestQuickSort.php
• EchoSrv -- TCP/IP server, threads
  • python: EchoSrv.py
  • ruby: EchoSrv.rb
  • perl: EchoSrv.pl
  • javascript: n/a
  • C#: EchoSrv.cs
  • F#: EchoSrv.fs
  • PHP: n/a
• FoldMapUCase -- higher order functions
  • python: FoldMapUCase.py
  • ruby: FoldMapUCase.rb
  • perl: FoldMapUCase.pl
  • javascript: FoldMapUCase.js TestFoldMapUCase.jst
  • C#: FoldMapUCase.cs TestFoldMapUCase.cs
  • F# (with NUnit invoked from C#): FoldMapUCase.fs TestFoldMapUCase.cs
  • PHP: FoldMapUCase.php TestFoldMapUCase.php
• Visitor -- classes, objects, inheritance, GoF visitor pattern
  • python: Visitor.py
  • ruby: Visitor.rb
  • perl: n/a
  • javascript: Visitor.html
  • C#: VisitorExample.cs
  • F#: visitor.fs
  • PHP: Visitor.php