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+'\"
+'\" Copyright (c) 1993 The Regents of the University of California.
+'\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
+'\"
+'\" See the file "license.terms" for information on usage and redistribution
+'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
+'\" 
+'\" RCS: @(#) $Id$
+'\" 
+.so man.macros
+.TH while n "" Tcl "Tcl Built-In Commands"
+.BS
+'\" Note:  do not modify the .SH NAME line immediately below!
+.SH NAME
+while \- Execute script repeatedly as long as a condition is met
+.SH SYNOPSIS
+\fBwhile \fItest body\fR
+.BE
+
+.SH DESCRIPTION
+.PP
+The \fBwhile\fR command evaluates \fItest\fR as an expression
+(in the same way that \fBexpr\fR evaluates its argument).
+The value of the expression must a proper boolean
+value; if it is a true value
+then \fIbody\fR is executed by passing it to the Tcl interpreter.
+Once \fIbody\fR has been executed then \fItest\fR is evaluated
+again, and the process repeats until eventually \fItest\fR
+evaluates to a false boolean value.  \fBContinue\fR
+commands may be executed inside \fIbody\fR to terminate the current
+iteration of the loop, and \fBbreak\fR
+commands may be executed inside \fIbody\fR to cause immediate
+termination of the \fBwhile\fR command.  The \fBwhile\fR command
+always returns an empty string.
+.PP
+Note: \fItest\fR should almost always be enclosed in braces.  If not,
+variable substitutions will be made before the \fBwhile\fR
+command starts executing, which means that variable changes
+made by the loop body will not be considered in the expression.
+This is likely to result in an infinite loop.  If \fItest\fR is
+enclosed in braces, variable substitutions are delayed until the
+expression is evaluated (before
+each loop iteration), so changes in the variables will be visible.
+For an example, try the following script with and without the braces
+around \fB$x<10\fR:
+.CS
+set x 0
+while {$x<10} {
+	puts "x is $x"
+	incr x
+}
+.CE
+
+.SH KEYWORDS
+boolean value, loop, test, while