evaluates test, then body, repetitively, until test first fails to give True.


  • While[test] does the loop with a null body.
  • If Break[] is generated in the evaluation of body, the While loop exits.
  • Continue[] exits the evaluation of body, and continues the loop.
  • Unless an explicit Return is used, the value returned by While is Null.
  • Note that in an example like i=0;While[i<0,tot+=f[i];i++] the roles of ; and , are reversed relative to C-like programming languages.
Introduced in 1988