| 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) 2001 Kevin B. Kenny <kennykb@acm.org>. All rights reserved. |
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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: lrange.n,v 1.17 2008/03/26 09:59:22 dkf Exp $ |
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| 10 | '\" |
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| 11 | .so man.macros |
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| 12 | .TH lrange n 7.4 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 | lrange \- Return one or more adjacent elements from a list |
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| 17 | .SH SYNOPSIS |
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| 18 | \fBlrange \fIlist first last\fR |
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| 19 | .BE |
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| 20 | |
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| 21 | .SH DESCRIPTION |
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| 22 | .PP |
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| 23 | \fIList\fR must be a valid Tcl list. This command will |
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| 24 | return a new list consisting of elements |
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| 25 | \fIfirst\fR through \fIlast\fR, inclusive. |
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| 26 | .VS 8.5 |
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| 27 | The index values \fIfirst\fR and \fIlast\fR are interpreted |
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| 28 | the same as index values for the command \fBstring index\fR, |
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| 29 | supporting simple index arithmetic and indices relative to the |
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| 30 | end of the list. |
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| 31 | .VE |
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| 32 | If \fIfirst\fR is less than zero, it is treated as if it were zero. |
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| 33 | If \fIlast\fR is greater than or equal to the number of elements |
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| 34 | in the list, then it is treated as if it were \fBend\fR. |
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| 35 | If \fIfirst\fR is greater than \fIlast\fR then an empty string |
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| 36 | is returned. |
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| 37 | Note: |
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| 38 | .QW "\fBlrange \fIlist first first\fR" |
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| 39 | does not always produce the same result as |
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| 40 | .QW "\fBlindex \fIlist first\fR" |
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| 41 | (although it often does for simple fields that are not enclosed in |
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| 42 | braces); it does, however, produce exactly the same results as |
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| 43 | .QW "\fBlist [lindex \fIlist first\fB]\fR" |
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| 44 | .SH EXAMPLES |
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| 45 | Selecting the first two elements: |
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| 46 | .CS |
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| 47 | % \fBlrange\fR {a b c d e} 0 1 |
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| 48 | a b |
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| 49 | .CE |
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| 50 | .PP |
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| 51 | Selecting the last three elements: |
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| 52 | .CS |
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| 53 | % \fBlrange\fR {a b c d e} end-2 end |
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| 54 | c d e |
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| 55 | .CE |
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| 56 | .PP |
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| 57 | Selecting everything except the first and last element: |
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| 58 | .CS |
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| 59 | % \fBlrange\fR {a b c d e} 1 end-1 |
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| 60 | b c d |
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| 61 | .CE |
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| 62 | .PP |
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| 63 | Selecting a single element with \fBlrange\fR is not the same as doing |
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| 64 | so with \fBlindex\fR: |
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| 65 | .CS |
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| 66 | % set var {some {elements to} select} |
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| 67 | some {elements to} select |
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| 68 | % lindex $var 1 |
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| 69 | elements to |
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| 70 | % \fBlrange\fR $var 1 1 |
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| 71 | {elements to} |
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| 72 | .CE |
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| 73 | |
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| 74 | .SH "SEE ALSO" |
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| 75 | list(n), lappend(n), lindex(n), linsert(n), llength(n), lsearch(n), |
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| 76 | lset(n), lreplace(n), lsort(n), |
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| 77 | .VS 8.5 |
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| 78 | string(n) |
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| 79 | .VE |
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| 80 | |
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| 81 | .SH KEYWORDS |
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| 82 | element, list, range, sublist |
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