Women in Technology

Article:		An Introduction to Haskell, Part 1: Why Haskell
Subject:		List comprehension in ruby too...
Date:		2007-05-24 08:11:27
From:		pmccann
Response to: List comprehension in python
The ruby's also a little funked: maybe something like... (1..10).find_all {|i| i % 2 == 0}

Showing messages 1 through 3 of 3.

• List comprehension in ruby too...
  2007-05-25 12:24:06  PaulBattley [View]
  
  
  You could also do it like this, to make it a bit more explicit:
  
  even = lambda{ |x| x % 2 == 0 }
  (1..10).select(&even)
  
  But it's more elegant in Haskell.

• List comprehension in ruby too...
  2007-05-26 03:23:29  paulk_asert [View]
  
  
  The Groovy equivalent to this looks very similar:
  
  (1..10).findAll {i -> i % 2 == 0}
  
  but if you look here:
  
  http://groovy.codehaus.org/Functional+Programming
  
  You can define the infinite stream of natural numbers which then lets you define all the even numbers as follows:
  
  def evennumbers = naturalnumbers.filter{ it % 2 == 0 }
  
  and then use it like this:
  
  assert [2 4 6 8 10] == evennumbers.take(5)
  

• While we're picking apart the examples...
  2007-05-28 14:45:08  Yakshavers [View]
  
  
  The C example takes the cake. How is the caller supposed to know how many elements are in the returned array, so as to avoid a buffer overrun?