2 '\" Copyright (c) 1993 The Regents of the University of California.
3 '\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
5 '\" See the file "license.terms" for information on usage and redistribution
6 '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
8 .TH for n "" Tcl "Tcl Built-In Commands"
9 .\" The -*- nroff -*- definitions below are for supplemental macros used
10 .\" in Tcl/Tk manual entries.
12 .\" .AP type name in/out ?indent?
13 .\" Start paragraph describing an argument to a library procedure.
14 .\" type is type of argument (int, etc.), in/out is either "in", "out",
15 .\" or "in/out" to describe whether procedure reads or modifies arg,
16 .\" and indent is equivalent to second arg of .IP (shouldn't ever be
17 .\" needed; use .AS below instead)
20 .\" Give maximum sizes of arguments for setting tab stops. Type and
21 .\" name are examples of largest possible arguments that will be passed
22 .\" to .AP later. If args are omitted, default tab stops are used.
25 .\" Start box enclosure. From here until next .BE, everything will be
26 .\" enclosed in one large box.
29 .\" End of box enclosure.
32 .\" Begin code excerpt.
37 .\" .VS ?version? ?br?
38 .\" Begin vertical sidebar, for use in marking newly-changed parts
39 .\" of man pages. The first argument is ignored and used for recording
40 .\" the version when the .VS was added, so that the sidebars can be
41 .\" found and removed when they reach a certain age. If another argument
42 .\" is present, then a line break is forced before starting the sidebar.
45 .\" End of vertical sidebar.
48 .\" Begin an indented unfilled display.
51 .\" End of indented unfilled display.
54 .\" Start of list of standard options for a Tk widget. The manpage
55 .\" argument defines where to look up the standard options; if
56 .\" omitted, defaults to "options". The options follow on successive
57 .\" lines, in three columns separated by tabs.
60 .\" End of list of standard options for a Tk widget.
62 .\" .OP cmdName dbName dbClass
63 .\" Start of description of a specific option. cmdName gives the
64 .\" option's name as specified in the class command, dbName gives
65 .\" the option's name in the option database, and dbClass gives
66 .\" the option's class in the option database.
69 .\" Print arg1 underlined, then print arg2 normally.
72 .\" Print arg1 in quotes, then arg2 normally (for trailing punctuation).
75 .\" Print an open parenthesis, arg1 in quotes, then arg2 normally
76 .\" (for trailing punctuation) and then a closing parenthesis.
78 .\" # Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
82 .\" # Start an argument description
86 . ie !"\\$2"" .TP \\n()Cu
91 \&\\$1 \\fI\\$2\\fP (\\$3)
104 .\" # define tabbing values for .AP
107 .if !"\\$1"" .nr )A \\w'\\$1'u+3n
110 .if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n
111 .nr )C \\n()Bu+\\w'(in/out)'u+2n
113 .AS Tcl_Interp Tcl_CreateInterp in/out
114 .\" # BS - start boxed text
115 .\" # ^y = starting y location
123 .if n \l'\\n(.lu\(ul'
126 .\" # BE - end boxed text (draw box now)
131 .ie n \l'\\n(^lu\(ul'
133 .\" Draw four-sided box normally, but don't draw top of
134 .\" box if the box started on an earlier page.
136 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
139 \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
146 .\" # VS - start vertical sidebar
147 .\" # ^Y = starting y location
148 .\" # ^v = 1 (for troff; for nroff this doesn't matter)
152 .ie n 'mc \s12\(br\s0
155 .\" # VE - end of vertical sidebar
163 \h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n'
170 .\" # Special macro to handle page bottom: finish off current
171 .\" # box/sidebar if in box/sidebar mode, then invoked standard
172 .\" # page bottom macro.
179 .\" Draw three-sided box if this is the box's first page,
180 .\" draw two sides but no top otherwise.
181 .ie !\\n(^b-1 \h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c
182 .el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c
185 .nr ^x \\n(^tu+1v-\\n(^Yu
186 \kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c
199 .\" # DS - begin display
205 .\" # DE - end display
211 .\" # SO - start of list of standard options
213 'ie '\\$1'' .ds So \\fBoptions\\fR
214 'el .ds So \\fB\\$1\\fR
215 .SH "STANDARD OPTIONS"
221 .\" # SE - end of list of standard options
226 See the \\*(So manual entry for details on the standard options.
228 .\" # OP - start of full description for a single option
233 Command-Line Name: \\fB\\$1\\fR
234 Database Name: \\fB\\$2\\fR
235 Database Class: \\fB\\$3\\fR
239 .\" # CS - begin code excerpt
245 .\" # CE - end code excerpt
250 .\" # UL - underline word
254 .\" # QW - apply quotation marks to word
256 .ie '\\*(lq'"' ``\\$1''\\$2
257 .\"" fix emacs highlighting
258 .el \\*(lq\\$1\\*(rq\\$2
260 .\" # PQ - apply parens and quotation marks to word
262 .ie '\\*(lq'"' (``\\$1''\\$2)\\$3
263 .\"" fix emacs highlighting
264 .el (\\*(lq\\$1\\*(rq\\$2)\\$3
266 .\" # QR - quoted range
268 .ie '\\*(lq'"' ``\\$1''\\-``\\$2''\\$3
269 .\"" fix emacs highlighting
270 .el \\*(lq\\$1\\*(rq\\-\\*(lq\\$2\\*(rq\\$3
272 .\" # MT - "empty" string
277 '\" Note: do not modify the .SH NAME line immediately below!
281 \fBfor \fIstart test next body\fR
286 \fBFor\fR is a looping command, similar in structure to the C
287 \fBfor\fR statement. The \fIstart\fR, \fInext\fR, and
288 \fIbody\fR arguments must be Tcl command strings, and \fItest\fR
289 is an expression string.
290 The \fBfor\fR command first invokes the Tcl interpreter to
291 execute \fIstart\fR. Then it repeatedly evaluates \fItest\fR as
292 an expression; if the result is non-zero it invokes the Tcl
293 interpreter on \fIbody\fR, then invokes the Tcl interpreter on \fInext\fR,
294 then repeats the loop. The command terminates when \fItest\fR evaluates
295 to 0. If a \fBcontinue\fR command is invoked within \fIbody\fR then
296 any remaining commands in the current execution of \fIbody\fR are skipped;
297 processing continues by invoking the Tcl interpreter on \fInext\fR, then
298 evaluating \fItest\fR, and so on. If a \fBbreak\fR command is invoked
301 then the \fBfor\fR command will
303 The operation of \fBbreak\fR and \fBcontinue\fR are similar to the
304 corresponding statements in C.
305 \fBFor\fR returns an empty string.
307 Note: \fItest\fR should almost always be enclosed in braces. If not,
308 variable substitutions will be made before the \fBfor\fR
309 command starts executing, which means that variable changes
310 made by the loop body will not be considered in the expression.
311 This is likely to result in an infinite loop. If \fItest\fR is
312 enclosed in braces, variable substitutions are delayed until the
313 expression is evaluated (before
314 each loop iteration), so changes in the variables will be visible.
315 See below for an example:
318 Print a line for each of the integers from 0 to 10:
321 \fBfor\fR {set x 0} {$x<10} {incr x} {
326 Either loop infinitely or not at all because the expression being
327 evaluated is actually the constant, or even generate an error! The
328 actual behaviour will depend on whether the variable \fIx\fR exists
329 before the \fBfor\fR command is run and whether its value is a value
330 that is less than or greater than/equal to ten, and this is because
331 the expression will be substituted before the \fBfor\fR command is
335 \fBfor\fR {set x 0} $x<10 {incr x} {
340 Print out the powers of two from 1 to 1024:
343 \fBfor\fR {set x 1} {$x<=1024} {set x [expr {$x * 2}]} {
348 break(n), continue(n), foreach(n), while(n)
350 boolean, for, iteration, loop