tcl7.6 User Commands - while
NAME
while - Execute script repeatedly as long as a condition is
met
SYNOPSIS
while test body
DESCRIPTION
The while command evaluates test as an expression (in the
same way that expr evaluates its argument). The value of
the expression must a proper boolean value; if it is a true
value then body is executed by passing it to the Tcl inter-
preter. Once body has been executed then test is evaluated
again, and the process repeats until eventually test evalu-
ates to a false boolean value. Continue commands may be
executed inside body to terminate the current iteration of
the loop, and break commands may be executed inside body to
cause immediate termination of the while command. The while
command always returns an empty string.
KEYWORDS
boolean value, loop, test, while