| 1 | '\" |
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| 2 | '\" Copyright (c) 1993 The Regents of the University of California. |
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| 3 | '\" Copyright (c) 1994-1996 Sun Microsystems, Inc. |
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| 4 | '\" Copyright (c) 2000 Ajuba Solutions. |
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| 5 | '\" |
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| 6 | '\" See the file "license.terms" for information on usage and redistribution |
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| 7 | '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. |
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| 8 | '\" |
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| 9 | '\" RCS: @(#) $Id: unset.n,v 1.13 2007/12/13 15:22:33 dgp Exp $ |
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| 10 | '\" |
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| 11 | .so man.macros |
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| 12 | .TH unset n 8.4 Tcl "Tcl Built-In Commands" |
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| 13 | .BS |
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| 14 | '\" Note: do not modify the .SH NAME line immediately below! |
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| 15 | .SH NAME |
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| 16 | unset \- Delete variables |
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| 17 | .SH SYNOPSIS |
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| 18 | \fBunset \fR?\fI\-nocomplain\fR? ?\fI\-\-\fR? ?\fIname name name ...\fR? |
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| 19 | .BE |
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| 20 | .SH DESCRIPTION |
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| 21 | .PP |
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| 22 | This command removes one or more variables. |
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| 23 | Each \fIname\fR is a variable name, specified in any of the |
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| 24 | ways acceptable to the \fBset\fR command. |
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| 25 | If a \fIname\fR refers to an element of an array then that |
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| 26 | element is removed without affecting the rest of the array. |
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| 27 | If a \fIname\fR consists of an array name with no parenthesized |
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| 28 | index, then the entire array is deleted. |
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| 29 | The \fBunset\fR command returns an empty string as result. |
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| 30 | If \fI\-nocomplain\fR is specified as the first argument, any possible |
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| 31 | errors are suppressed. The option may not be abbreviated, in order to |
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| 32 | disambiguate it from possible variable names. The option \fI\-\-\fR |
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| 33 | indicates the end of the options, and should be used if you wish to |
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| 34 | remove a variable with the same name as any of the options. |
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| 35 | If an error occurs, any variables after the named one causing the error not |
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| 36 | deleted. An error can occur when the named variable does not exist, or the |
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| 37 | name refers to an array element but the variable is a scalar, or the name |
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| 38 | refers to a variable in a non-existent namespace. |
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| 39 | .SH EXAMPLE |
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| 40 | Create an array containing a mapping from some numbers to their |
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| 41 | squares and remove the array elements for non-prime numbers: |
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| 42 | .CS |
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| 43 | array set squares { |
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| 44 | 1 1 6 36 |
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| 45 | 2 4 7 49 |
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| 46 | 3 9 8 64 |
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| 47 | 4 16 9 81 |
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| 48 | 5 25 10 100 |
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| 49 | } |
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| 50 | |
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| 51 | puts "The squares are:" |
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| 52 | parray squares |
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| 53 | |
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| 54 | \fBunset\fR squares(1) squares(4) squares(6) |
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| 55 | \fBunset\fR squares(8) squares(9) squares(10) |
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| 56 | |
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| 57 | puts "The prime squares are:" |
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| 58 | parray squares |
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| 59 | .CE |
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| 60 | .SH "SEE ALSO" |
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| 61 | set(n), trace(n), upvar(n) |
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| 62 | .SH KEYWORDS |
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| 63 | remove, variable |
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