'\" '\" Copyright (c) 1993 The Regents of the University of California. '\" Copyright (c) 1994-1996 Sun Microsystems, Inc. '\" Copyright (c) 2000 Ajuba Solutions. '\" '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. '\" '\" RCS: @(#) $Id: unset.n,v 1.5.18.3 2010/04/18 21:34:57 dkf Exp $ '\" .so man.macros .TH unset n 8.4 Tcl "Tcl Built-In Commands" .BS '\" Note: do not modify the .SH NAME line immediately below! .SH NAME unset \- Delete variables .SH SYNOPSIS \fBunset \fR?\fI\-nocomplain\fR? ?\fI\-\-\fR? ?\fIname name name ...\fR? .BE .SH DESCRIPTION .PP This command removes one or more variables. Each \fIname\fR is a variable name, specified in any of the ways acceptable to the \fBset\fR command. If a \fIname\fR refers to an element of an array then that element is removed without affecting the rest of the array. If a \fIname\fR consists of an array name with no parenthesized index, then the entire array is deleted. The \fBunset\fR command returns an empty string as result. .VS 8.4 If \fI\-nocomplain\fR is specified as the first argument, any possible errors are suppressed. The option may not be abbreviated, in order to disambiguate it from possible variable names. The option \fI\-\-\fR indicates the end of the options, and should be used if you wish to remove a variable with the same name as any of the options. .VE 8.4 If an error occurs, any variables after the named one causing the error are not deleted. An error can occur when the named variable doesn't exist, or the name refers to an array element but the variable is a scalar, or the name refers to a variable in a non-existent namespace. .SH EXAMPLE Create an array containing a mapping from some numbers to their squares and remove the array elements for non-prime numbers: .CS array set squares { 1 1 6 36 2 4 7 49 3 9 8 64 4 16 9 81 5 25 10 100 } puts "The squares are:" parray squares \fBunset\fR squares(1) squares(4) squares(6) \fBunset\fR squares(8) squares(9) squares(10) puts "The prime squares are:" parray squares .CE .SH "SEE ALSO" set(n), trace(n), upvar(n) .SH KEYWORDS remove, variable