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'\"
'\" Copyright (c) 1993 The Regents of the University of California.
'\" Copyright (c) 1994-1996 Sun Microsystems, Inc.
'\" Copyright (c) 2001 Kevin B. Kenny <kennykb@acm.org>. All rights reserved.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\"
'\" RCS: @(#) $Id: lrange.n,v 1.18 2008/06/29 22:28:24 dkf Exp $
'\"
.so man.macros
.TH lrange n 7.4 Tcl "Tcl Built-In Commands"
.BS
'\" Note: do not modify the .SH NAME line immediately below!
.SH NAME
lrange \- Return one or more adjacent elements from a list
.SH SYNOPSIS
\fBlrange \fIlist first last\fR
.BE
.SH DESCRIPTION
.PP
\fIList\fR must be a valid Tcl list. This command will
return a new list consisting of elements
\fIfirst\fR through \fIlast\fR, inclusive.
The index values \fIfirst\fR and \fIlast\fR are interpreted
the same as index values for the command \fBstring index\fR,
supporting simple index arithmetic and indices relative to the
end of the list.
If \fIfirst\fR is less than zero, it is treated as if it were zero.
If \fIlast\fR is greater than or equal to the number of elements
in the list, then it is treated as if it were \fBend\fR.
If \fIfirst\fR is greater than \fIlast\fR then an empty string
is returned.
Note:
.QW "\fBlrange \fIlist first first\fR"
does not always produce the same result as
.QW "\fBlindex \fIlist first\fR"
(although it often does for simple fields that are not enclosed in
braces); it does, however, produce exactly the same results as
.QW "\fBlist [lindex \fIlist first\fB]\fR"
.SH EXAMPLES
Selecting the first two elements:
.CS
% \fBlrange\fR {a b c d e} 0 1
a b
.CE
.PP
Selecting the last three elements:
.CS
% \fBlrange\fR {a b c d e} end-2 end
c d e
.CE
.PP
Selecting everything except the first and last element:
.CS
% \fBlrange\fR {a b c d e} 1 end-1
b c d
.CE
.PP
Selecting a single element with \fBlrange\fR is not the same as doing
so with \fBlindex\fR:
.CS
% set var {some {elements to} select}
some {elements to} select
% lindex $var 1
elements to
% \fBlrange\fR $var 1 1
{elements to}
.CE
.SH "SEE ALSO"
list(n), lappend(n), lindex(n), linsert(n), llength(n), lsearch(n),
lset(n), lreplace(n), lsort(n),
string(n)
.SH KEYWORDS
element, list, range, sublist
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