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'\" Copyright (c) 1993 The Regents of the University of California.
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'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
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'\" See the file "license.terms" for information on usage and redistribution
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'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
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'\" RCS: @(#) $Id: set.n,v 1.7 2006/08/09 10:06:28 dkf Exp $
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.TH set n "" Tcl "Tcl Built-In Commands"
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'\" Note: do not modify the .SH NAME line immediately below!
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set \- Read and write variables
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\fBset \fIvarName \fR?\fIvalue\fR?
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Returns the value of variable \fIvarName\fR.
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If \fIvalue\fR is specified, then set
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the value of \fIvarName\fR to \fIvalue\fR, creating a new variable
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if one doesn't already exist, and return its value.
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If \fIvarName\fR contains an open parenthesis and ends with a
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close parenthesis, then it refers to an array element: the characters
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before the first open parenthesis are the name of the array,
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and the characters between the parentheses are the index within the array.
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Otherwise \fIvarName\fR refers to a scalar variable.
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If \fIvarName\fR includes namespace qualifiers
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(in the array name if it refers to an array element), or if \fIvarName\fR
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is unqualified (does not include the names of any containing namespaces)
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but no procedure is active,
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\fIvarName\fR refers to a namespace variable
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resolved according to the rules described under \fBNAME RESOLUTION\fR in
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the \fBnamespace\fR manual page.
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If a procedure is active and \fIvarName\fR is unqualified, then
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\fIvarName\fR refers to a parameter or local variable of the procedure,
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unless \fIvarName\fR was declared to resolve differently through one of the
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\fBglobal\fR, \fBvariable\fR or \fBupvar\fR commands.
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Store a random number in the variable \fIr\fR:
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\fBset\fR r [expr {rand()}]
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Store a short message in an array element:
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\fBset\fR anAry(msg) "Hello, World!"
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Store a short message in an array element specified by a variable:
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\fBset\fR elemName "msg"
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\fBset\fR anAry($elemName) "Hello, World!"
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Copy a value into the variable \fIout\fR from a variable whose name is
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stored in the \fIvbl\fR (note that it is often easier to use arrays in
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practice instead of doing double-dereferencing):
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\fBset\fR in0 "small random"
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\fBset\fR in1 "large random"
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\fBset\fR vbl in[expr {rand() >= 0.5}]
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\fBset\fR out [\fBset\fR $vbl]
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expr(n), global(n), namespace(n), proc(n), trace(n), unset(n), upvar(n), variable(n)
added
removed
doc/set.n
