Perl "cut" equivalent in R

 -----Original Message-----
 From: r-help-bounces at r-project.org
 [mailto:r-help-bounces at r-project.org] On Behalf Of Martin Maechler
 Sent: Friday, December 10, 2010 8:54 AM
 To: Steve Lianoglou
 Cc: r-help at r-project.org
 Subject: Re: [R] Perl "cut" equivalent in R

 >>>>>  "SL" == Steve Lianoglou<mailinglist.honeypot at gmail.com>
 >>>>>      on Mon, 6 Dec 2010 14:21:59 -0500 writes:

     >>>  if(FALSE) { stuff your don't want executed          }
     >>>

     >>

 >  Switching a block of code off/on with editing a single

     >>  character may be done using 0/1 instead of FALSE/TRUE.

     SL>  Or even F/T

 Bad Idea:

   F<- 1

Another approach is to write the following function
     dontRun<- function(expr) {}
and replace that
     if (FALSE) { ... questionable code ... }
with
     dontRun( {... questionable code ...} )
If you do want the questionable code to run,
redefine dontRun to be
     dontRun<- function(expr) { expr }

You can use this approach to put assertion tests
into your code that only get run when the assertion
function is defined to do something.