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author | William Joye <wjoye@cfa.harvard.edu> | 2016-12-21 22:13:18 (GMT) |
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committer | William Joye <wjoye@cfa.harvard.edu> | 2016-12-21 22:13:18 (GMT) |
commit | 07e464099b99459d0a37757771791598ef3395d9 (patch) | |
tree | 4ba7d8aad13735e52f59bdce7ca5ba3151ebd7e3 /tcl8.6/doc/lindex.n | |
parent | deb3650e37f26f651f280e480c4df3d7dde87bae (diff) | |
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new subtree for tcl/tk
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-rw-r--r-- | tcl8.6/doc/lindex.n | 125 |
1 files changed, 0 insertions, 125 deletions
diff --git a/tcl8.6/doc/lindex.n b/tcl8.6/doc/lindex.n deleted file mode 100644 index d5605bc..0000000 --- a/tcl8.6/doc/lindex.n +++ /dev/null @@ -1,125 +0,0 @@ -'\" -'\" Copyright (c) 1993 The Regents of the University of California. -'\" Copyright (c) 1994-1996 Sun Microsystems, Inc. -'\" Copyright (c) 2001 by 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. -'\" -.TH lindex n 8.4 Tcl "Tcl Built-In Commands" -.so man.macros -.BS -'\" Note: do not modify the .SH NAME line immediately below! -.SH NAME -lindex \- Retrieve an element from a list -.SH SYNOPSIS -\fBlindex \fIlist ?index ...?\fR -.BE -.SH DESCRIPTION -.PP -The \fBlindex\fR command accepts a parameter, \fIlist\fR, which -it treats as a Tcl list. It also accepts zero or more \fIindices\fR into -the list. The indices may be presented either consecutively on the -command line, or grouped in a -Tcl list and presented as a single argument. -.PP -If no indices are presented, the command takes the form: -.PP -.CS -\fBlindex \fIlist\fR -.CE -.PP -or -.PP -.CS -\fBlindex \fIlist\fR {} -.CE -.PP -In this case, the return value of \fBlindex\fR is simply the value of the -\fIlist\fR parameter. -.PP -When presented with a single index, the \fBlindex\fR command -treats \fIlist\fR as a Tcl list and returns the -\fIindex\fR'th element from it (0 refers to the first element of the list). -In extracting the element, \fBlindex\fR observes the same rules -concerning braces and quotes and backslashes as the Tcl command -interpreter; however, variable -substitution and command substitution do not occur. -If \fIindex\fR is negative or greater than or equal to the number -of elements in \fIvalue\fR, then an empty -string is returned. -The interpretation of each simple \fIindex\fR value is the same as -for the command \fBstring index\fR, supporting simple index -arithmetic and indices relative to the end of the list. -.PP -If additional \fIindex\fR arguments are supplied, then each argument is -used in turn to select an element from the previous indexing operation, -allowing the script to select elements from sublists. The command, -.PP -.CS -\fBlindex\fR $a 1 2 3 -.CE -.PP -or -.PP -.CS -\fBlindex\fR $a {1 2 3} -.CE -.PP -is synonymous with -.PP -.CS -\fBlindex\fR [\fBlindex\fR [\fBlindex\fR $a 1] 2] 3 -.CE -.SH EXAMPLES -.PP -Lists can be indexed into from either end: -.PP -.CS -\fBlindex\fR {a b c} 0 - \fI\(-> a\fR -\fBlindex\fR {a b c} 2 - \fI\(-> c\fR -\fBlindex\fR {a b c} end - \fI\(-> c\fR -\fBlindex\fR {a b c} end-1 - \fI\(-> b\fR -.CE -.PP -Lists or sequences of indices allow selection into lists of lists: -.PP -.CS -\fBlindex\fR {a b c} - \fI\(-> a b c\fR -\fBlindex\fR {a b c} {} - \fI\(-> a b c\fR -\fBlindex\fR {{a b c} {d e f} {g h i}} 2 1 - \fI\(-> h\fR -\fBlindex\fR {{a b c} {d e f} {g h i}} {2 1} - \fI\(-> h\fR -\fBlindex\fR {{{a b} {c d}} {{e f} {g h}}} 1 1 0 - \fI\(-> g\fR -\fBlindex\fR {{{a b} {c d}} {{e f} {g h}}} {1 1 0} - \fI\(-> g\fR -.CE -.PP -List indices may also perform limited computation, adding or subtracting fixed -amounts from other indices: -.PP -.CS -set idx 1 -\fBlindex\fR {a b c d e f} $idx+2 - \fI\(-> d\fR -set idx 3 -\fBlindex\fR {a b c d e f} $idx+2 - \fI\(-> f\fR -.CE -.SH "SEE ALSO" -list(n), lappend(n), linsert(n), llength(n), lsearch(n), -lset(n), lsort(n), lrange(n), lreplace(n), -string(n) -.SH KEYWORDS -element, index, list -'\"Local Variables: -'\"mode: nroff -'\"End: |