While

While[test, body] 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 Return[ ] or Throw[ ] are generated, the final value returned by While is Null.

Example: i=0; While[i < 0, tot += f[i]; i++]. Note that the roles of ; and , are reversed relative to the C programming language.

See Section 2.6.9.

See also: Do, For, NestWhile, Nest, Fold, Select, Throw.

New in Version 1.

Further Examples