69 lines
2.2 KiB
Plaintext
69 lines
2.2 KiB
Plaintext
'\"
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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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'\" Copyright (c) 2000 Ajuba Solutions.
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'\"
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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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'\"
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.TH unset n 8.4 Tcl "Tcl Built-In Commands"
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.so man.macros
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.BS
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'\" Note: do not modify the .SH NAME line immediately below!
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.SH NAME
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unset \- Delete variables
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.SH SYNOPSIS
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\fBunset \fR?\fB\-nocomplain\fR? ?\fB\-\-\fR? ?\fIname name name ...\fR?
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.BE
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.SH DESCRIPTION
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.PP
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This command removes one or more variables.
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Each \fIname\fR is a variable name, specified in any of the
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ways acceptable to the \fBset\fR command.
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If a \fIname\fR refers to an element of an array then that
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element is removed without affecting the rest of the array.
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If a \fIname\fR consists of an array name with no parenthesized
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index, then the entire array is deleted.
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The \fBunset\fR command returns an empty string as result.
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If \fB\-nocomplain\fR is specified as the first argument, any possible
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errors are suppressed. The option may not be abbreviated, in order to
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disambiguate it from possible variable names. The option \fB\-\-\fR
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indicates the end of the options, and should be used if you wish to
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remove a variable with the same name as any of the options.
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If an error occurs during variable deletion, any variables after the named one
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causing the error are not
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deleted. An error can occur when the named variable does not exist, or the
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name refers to an array element but the variable is a scalar, or the name
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refers to a variable in a non-existent namespace.
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.SH EXAMPLE
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.PP
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Create an array containing a mapping from some numbers to their
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squares and remove the array elements for non-prime numbers:
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.PP
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.CS
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array set squares {
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1 1 6 36
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2 4 7 49
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3 9 8 64
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4 16 9 81
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5 25 10 100
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}
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puts "The squares are:"
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parray squares
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\fBunset\fR squares(1) squares(4) squares(6)
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\fBunset\fR squares(8) squares(9) squares(10)
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puts "The prime squares are:"
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parray squares
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.CE
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.SH "SEE ALSO"
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set(n), trace(n), upvar(n)
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.SH KEYWORDS
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remove, variable
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'\" Local Variables:
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'\" mode: nroff
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'\" fill-column: 78
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'\" End:
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