SWF Humor

Funny little blast from the (Spring Web Flow) past. Back in 2006 while working on Spring Web Flow 1.0 we needed an exception class signaling a failure to parse a flow execution key. Keith Donald and myself jokingly considered calling it the FuckedUpFlowExecutionKeyException but ultimately settled for BadlyFormattedFlowExecutionKeyException. Indeed, it would be quite painful if a user was presented with a FuckedUpFlowExecutionKeyException stack trace after having accidentally corrupted the key in the URL of his browser. :-)

The joke continued for a little bit with the following piece of JavaDoc that you can find in the Spring Web Flow 1.0 source code:

package org.springframework.webflow.execution.repository;

/**
 * Thrown when an encoded flow execution key is badly formatted and could not be
 * parsed. We debated calling this the FuckedUpFlowExecutionKeyException.
 * 
 * @author Keith Donald
 * @author Erwin Vervaet
 */
public class BadlyFormattedFlowExecutionKeyException extends FlowExecutionRepositoryException {

This was not enough however, a particularly sensitive person actually complained about Spring Web Flow using offensive language! In the end this bit of nostalgia was kicked out in the 1.0.1 release. Still makes for a fun anecdote however! ;-)

Q_rsqrt

I still remember encountering the following piece of code while browsing through the Quake 3 source code back in 2005:

float Q_rsqrt( float number )
{
  long i;
  float x2, y;
  const float threehalfs = 1.5F;

  x2 = number * 0.5F;
  y  = number;
  i  = * ( long * ) &y;  // evil floating point bit level hacking
  i  = 0x5f3759df - ( i >> 1 ); // what the fuck?
  y  = * ( float * ) &i;
  y  = y * ( threehalfs - ( x2 * y * y ) ); // 1st iteration
  // y  = y * ( threehalfs - ( x2 * y * y ) ); // 2nd iteration, this can be removed

  #ifndef Q3_VM
  #ifdef __linux__
    assert( !isnan(y) ); // bk010122 - FPE?
  #endif
  #endif
  return y;
}

That comment on line 10 pretty much sums it up: WTF!?!?

I again ran across this piece of code while browsing an amuzing list of the best comments in source code you've encountered, over on Stackoverflow. It turns out the original author of this illustrious piece of code is still unknown (it's not John Carmack as you might have assumed). A nice write-up of the likely history of this hack can be found on Beyond3D. Interesting reading for sure!
UPDATE: The original author is actually known and it is Greg Walsh. Wikipedia also has a lot of background.

Talking about funny comments in code, my personal favorite from the Stackoverflow list must be the following:

stop(); // Hammertime!

Not so much the comment, but the german version really cracked me up!