'\"
'\" Generated from file '/usr/obj/ports/tcllib-1.10/tcllib-1.10/modules/page/page_util_flow.man' by tcllib/doctools with format 'nroff'
'\" Copyright (c) 2007 Andreas Kupries <andreas_kupries@users.sourceforge.net>
'\"
'\" The definitions below are for supplemental macros used in Tcl/Tk
'\" manual entries.
'\"
'\" .AP type name in/out ?indent?
'\"	Start paragraph describing an argument to a library procedure.
'\"	type is type of argument (int, etc.), in/out is either "in", "out",
'\"	or "in/out" to describe whether procedure reads or modifies arg,
'\"	and indent is equivalent to second arg of .IP (shouldn't ever be
'\"	needed;  use .AS below instead)
'\"
'\" .AS ?type? ?name?
'\"	Give maximum sizes of arguments for setting tab stops.  Type and
'\"	name are examples of largest possible arguments that will be passed
'\"	to .AP later.  If args are omitted, default tab stops are used.
'\"
'\" .BS
'\"	Start box enclosure.  From here until next .BE, everything will be
'\"	enclosed in one large box.
'\"
'\" .BE
'\"	End of box enclosure.
'\"
'\" .CS
'\"	Begin code excerpt.
'\"
'\" .CE
'\"	End code excerpt.
'\"
'\" .VS ?version? ?br?
'\"	Begin vertical sidebar, for use in marking newly-changed parts
'\"	of man pages.  The first argument is ignored and used for recording
'\"	the version when the .VS was added, so that the sidebars can be
'\"	found and removed when they reach a certain age.  If another argument
'\"	is present, then a line break is forced before starting the sidebar.
'\"
'\" .VE
'\"	End of vertical sidebar.
'\"
'\" .DS
'\"	Begin an indented unfilled display.
'\"
'\" .DE
'\"	End of indented unfilled display.
'\"
'\" .SO
'\"	Start of list of standard options for a Tk widget.  The
'\"	options follow on successive lines, in four columns separated
'\"	by tabs.
'\"
'\" .SE
'\"	End of list of standard options for a Tk widget.
'\"
'\" .OP cmdName dbName dbClass
'\"	Start of description of a specific option.  cmdName gives the
'\"	option's name as specified in the class command, dbName gives
'\"	the option's name in the option database, and dbClass gives
'\"	the option's class in the option database.
'\"
'\" .UL arg1 arg2
'\"	Print arg1 underlined, then print arg2 normally.
'\"
'\" RCS: @(#) $Id: man.macros,v 1.1 2006/07/01 03:37:56 andreas_kupries Exp $
'\"
'\"	# Set up traps and other miscellaneous stuff for Tcl/Tk man pages.
.if t .wh -1.3i ^B
.nr ^l \n(.l
.ad b
'\"	# Start an argument description
.de AP
.ie !"\\$4"" .TP \\$4
.el \{\
.   ie !"\\$2"" .TP \\n()Cu
.   el          .TP 15
.\}
.ta \\n()Au \\n()Bu
.ie !"\\$3"" \{\
\&\\$1	\\fI\\$2\\fP	(\\$3)
.\".b
.\}
.el \{\
.br
.ie !"\\$2"" \{\
\&\\$1	\\fI\\$2\\fP
.\}
.el \{\
\&\\fI\\$1\\fP
.\}
.\}
..
'\"	# define tabbing values for .AP
.de AS
.nr )A 10n
.if !"\\$1"" .nr )A \\w'\\$1'u+3n
.nr )B \\n()Au+15n
.\"
.if !"\\$2"" .nr )B \\w'\\$2'u+\\n()Au+3n
.nr )C \\n()Bu+\\w'(in/out)'u+2n
..
.AS Tcl_Interp Tcl_CreateInterp in/out
'\"	# BS - start boxed text
'\"	# ^y = starting y location
'\"	# ^b = 1
.de BS
.br
.mk ^y
.nr ^b 1u
.if n .nf
.if n .ti 0
.if n \l'\\n(.lu\(ul'
.if n .fi
..
'\"	# BE - end boxed text (draw box now)
.de BE
.nf
.ti 0
.mk ^t
.ie n \l'\\n(^lu\(ul'
.el \{\
.\"	Draw four-sided box normally, but don't draw top of
.\"	box if the box started on an earlier page.
.ie !\\n(^b-1 \{\
\h'-1.5n'\L'|\\n(^yu-1v'\l'\\n(^lu+3n\(ul'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
.\}
.el \}\
\h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\l'|0u-1.5n\(ul'
.\}
.\}
.fi
.br
.nr ^b 0
..
'\"	# VS - start vertical sidebar
'\"	# ^Y = starting y location
'\"	# ^v = 1 (for troff;  for nroff this doesn't matter)
.de VS
.if !"\\$2"" .br
.mk ^Y
.ie n 'mc \s12\(br\s0
.el .nr ^v 1u
..
'\"	# VE - end of vertical sidebar
.de VE
.ie n 'mc
.el \{\
.ev 2
.nf
.ti 0
.mk ^t
\h'|\\n(^lu+3n'\L'|\\n(^Yu-1v\(bv'\v'\\n(^tu+1v-\\n(^Yu'\h'-|\\n(^lu+3n'
.sp -1
.fi
.ev
.\}
.nr ^v 0
..
'\"	# Special macro to handle page bottom:  finish off current
'\"	# box/sidebar if in box/sidebar mode, then invoked standard
'\"	# page bottom macro.
.de ^B
.ev 2
'ti 0
'nf
.mk ^t
.if \\n(^b \{\
.\"	Draw three-sided box if this is the box's first page,
.\"	draw two sides but no top otherwise.
.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
.el \h'-1.5n'\L'|\\n(^yu-1v'\h'\\n(^lu+3n'\L'\\n(^tu+1v-\\n(^yu'\h'|0u'\c
.\}
.if \\n(^v \{\
.nr ^x \\n(^tu+1v-\\n(^Yu
\kx\h'-\\nxu'\h'|\\n(^lu+3n'\ky\L'-\\n(^xu'\v'\\n(^xu'\h'|0u'\c
.\}
.bp
'fi
.ev
.if \\n(^b \{\
.mk ^y
.nr ^b 2
.\}
.if \\n(^v \{\
.mk ^Y
.\}
..
'\"	# DS - begin display
.de DS
.RS
.nf
.sp
..
'\"	# DE - end display
.de DE
.fi
.RE
.sp
..
'\"	# SO - start of list of standard options
.de SO
.SH "STANDARD OPTIONS"
.LP
.nf
.ta 4c 8c 12c
.ft B
..
'\"	# SE - end of list of standard options
.de SE
.fi
.ft R
.LP
See the \\fBoptions\\fR manual entry for details on the standard options.
..
'\"	# OP - start of full description for a single option
.de OP
.LP
.nf
.ta 4c
Command-Line Name:	\\fB\\$1\\fR
Database Name:	\\fB\\$2\\fR
Database Class:	\\fB\\$3\\fR
.fi
.IP
..
'\"	# CS - begin code excerpt
.de CS
.RS
.nf
.ta .25i .5i .75i 1i
..
'\"	# CE - end code excerpt
.de CE
.fi
.RE
..
.de UL
\\$1\l'|0\(ul'\\$2
..
.TH "page_util_flow" n 1.0 page "Parser generator tools"
.BS
.SH NAME
page_util_flow \- page dataflow/treewalker utility
.SH SYNOPSIS
package require \fBpage::util::flow  ?0.1?\fR
.sp
package require \fBsnit \fR
.sp
\fB::page::util::flow\fR \fIstart\fR \fIflowvar\fR \fInodevar\fR \fIscript\fR
.sp
\fIflow\fR \fBvisit\fR \fInode\fR
.sp
\fIflow\fR \fBvisitl\fR \fInodelist\fR
.sp
\fIflow\fR \fBvisita\fR \fInode\fR...
.sp
.BE
.SH DESCRIPTION
.PP
This package provides a single utility command for easy dataflow based
manipulation of arbitrary data structures, especially abstract syntax
trees.
.SH API
.TP
\fB::page::util::flow\fR \fIstart\fR \fIflowvar\fR \fInodevar\fR \fIscript\fR
This command contains the core logic to drive the walking of an
arbitrary data structure which can partitioned into separate
parts. Examples of such structures are trees and graphs.
.sp
The command makes no assumptions at all about the API of the structure
to be walked, except that that its parts, here called \fInodes\fR,
are identified by strings. These strings are taken as is, from the
arguments, and the body, and handed back to the body, without
modification.
.sp
Access to the actual data structure, and all decisions regarding which
nodes to visit in what order are delegated to the body of the loop,
i.e. the \fIscript\fR.
.sp
The body is invoked first for the nodes in the start-set specified via
\fIstart\fR), and from then on for the nodes the body has requested to
be visited. The command stops when the set of nodes to visit becomes
empty. Note that a node can be visited more than once. The body has
complete control about this.
.sp
The body is invoked in the context of the caller. The variable named
by \fInodevar\fR will be set to the current node, and the variable
named by \fIflowvar\fR will be set to the command of the flow object
through which the body can request the nodes to visit next. The API
provided by this object is described in the next section,
\fBFLOW API\fR.
.sp
Note that the command makes no promises regarding the order in which
nodes are visited, excpt that the nodes requested to be visited by the
current iteration will be visited afterward, in some order.
.PP
.SH "FLOW API"
This section describes the API provided by the flow object made
accessible to the body script of \fB::page::util::flow\fR.
.TP
\fIflow\fR \fBvisit\fR \fInode\fR
Invoking this method requests that the node \fIn\fR is visited after
the current iteration.
.TP
\fIflow\fR \fBvisitl\fR \fInodelist\fR
Invoking this method requests that all the nodes found in the list
\fInodelist\fR are visited after the current iteration.
.TP
\fIflow\fR \fBvisita\fR \fInode\fR...
This is the variadic arguments form of the method \fBvisitl\fR, see
above.
.PP
.SH "BUGS, IDEAS, FEEDBACK"
This document, will undoubtedly contain bugs and other problems.
Please report such in the category \fIpage\fR of the
\fITcllib SF Trackers\fR [http://sourceforge.net/tracker/?group_id=12883].
Please also report any ideas for enhancements you may have.
.SH KEYWORDS
dataflow, graph walking, page, parser generator, text processing, tree walking
.SH COPYRIGHT
.nf
Copyright (c) 2007 Andreas Kupries <andreas_kupries@users.sourceforge.net>

.fi