'\" '\" Generated from file 'to\&.inc' by tcllib/doctools with format 'nroff' '\" Copyright (c) 2009 Andreas Kupries '\" .TH "pt::peg::to::tclparam" 3tcl 1\&.0\&.3 tcllib "Parser Tools" .\" The -*- nroff -*- 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 ?manpage? .\" Start of list of standard options for a Tk widget. The manpage .\" argument defines where to look up the standard options; if .\" omitted, defaults to "options". The options follow on successive .\" lines, in three 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. .\" .\" .QW arg1 ?arg2? .\" Print arg1 in quotes, then arg2 normally (for trailing punctuation). .\" .\" .PQ arg1 ?arg2? .\" Print an open parenthesis, arg1 in quotes, then arg2 normally .\" (for trailing punctuation) and then a closing parenthesis. .\" .\" # 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 'ie '\\$1'' .ds So \\fBoptions\\fR 'el .ds So \\fB\\$1\\fR .SH "STANDARD OPTIONS" .LP .nf .ta 5.5c 11c .ft B .. .\" # SE - end of list of standard options .de SE .fi .ft R .LP See the \\*(So 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 .. .\" # UL - underline word .de UL \\$1\l'|0\(ul'\\$2 .. .\" # QW - apply quotation marks to word .de QW .ie '\\*(lq'"' ``\\$1''\\$2 .\"" fix emacs highlighting .el \\*(lq\\$1\\*(rq\\$2 .. .\" # PQ - apply parens and quotation marks to word .de PQ .ie '\\*(lq'"' (``\\$1''\\$2)\\$3 .\"" fix emacs highlighting .el (\\*(lq\\$1\\*(rq\\$2)\\$3 .. .\" # QR - quoted range .de QR .ie '\\*(lq'"' ``\\$1''\\-``\\$2''\\$3 .\"" fix emacs highlighting .el \\*(lq\\$1\\*(rq\\-\\*(lq\\$2\\*(rq\\$3 .. .\" # MT - "empty" string .de MT .QW "" .. .BS .SH NAME pt::peg::to::tclparam \- PEG Conversion\&. Write TCLPARAM format .SH SYNOPSIS package require \fBTcl 8\&.5\fR .sp package require \fBpt::peg::to::tclparam ?1\&.0\&.3?\fR .sp \fBpt::peg::to::tclparam\fR \fBreset\fR .sp \fBpt::peg::to::tclparam\fR \fBconfigure\fR .sp \fBpt::peg::to::tclparam\fR \fBconfigure\fR \fIoption\fR .sp \fBpt::peg::to::tclparam\fR \fBconfigure\fR \fIoption\fR \fIvalue\fR\&.\&.\&. .sp \fBpt::peg::to::tclparam\fR \fBconvert\fR \fIserial\fR .sp .BE .SH DESCRIPTION .PP Are you lost ? Do you have trouble understanding this document ? In that case please read the overview provided by the \fIIntroduction to Parser Tools\fR\&. This document is the entrypoint to the whole system the current package is a part of\&. .PP This package implements the converter from parsing expression grammars to TCLPARAM markup\&. .PP It resides in the Export section of the Core Layer of Parser Tools, and can be used either directly with the other packages of this layer, or indirectly through the export manager provided by \fBpt::peg::export\fR\&. The latter is intented for use in untrusted environments and done through the corresponding export plugin \fBpt::peg::export::tclparam\fR sitting between converter and export manager\&. .PP IMAGE: arch_core_eplugins .PP .SH API The API provided by this package satisfies the specification of the Converter API found in the \fIParser Tools Export API\fR specification\&. .TP \fBpt::peg::to::tclparam\fR \fBreset\fR This command resets the configuration of the package to its default settings\&. .TP \fBpt::peg::to::tclparam\fR \fBconfigure\fR This command returns a dictionary containing the current configuration of the package\&. .TP \fBpt::peg::to::tclparam\fR \fBconfigure\fR \fIoption\fR This command returns the current value of the specified configuration \fIoption\fR of the package\&. For the set of legal options, please read the section \fBOptions\fR\&. .TP \fBpt::peg::to::tclparam\fR \fBconfigure\fR \fIoption\fR \fIvalue\fR\&.\&.\&. This command sets the given configuration \fIoption\fRs of the package, to the specified \fIvalue\fRs\&. For the set of legal options, please read the section \fBOptions\fR\&. .TP \fBpt::peg::to::tclparam\fR \fBconvert\fR \fIserial\fR This command takes the canonical serialization of a parsing expression grammar, as specified in section \fBPEG serialization format\fR, and contained in \fIserial\fR, and generates TCLPARAM markup encoding the grammar, per the current package configuration\&. The created string is then returned as the result of the command\&. .PP .SH OPTIONS The converter to Tcl/PARAM markup recognizes the following configuration variables and changes its behaviour as they specify\&. .TP \fB-template\fR string The value of this configuration variable is a string into which to put the generated text and the other configuration settings\&. The various locations for user-data are expected to be specified with the placeholders listed below\&. The default value is "\fB@code@\fR"\&. .RS .TP \fB@user@\fR To be replaced with the value of the configuration variable \fB-user\fR\&. .TP \fB@format@\fR To be replaced with the the constant \fBTcl/PARAM\fR\&. .TP \fB@file@\fR To be replaced with the value of the configuration variable \fB-file\fR\&. .TP \fB@name@\fR To be replaced with the value of the configuration variable \fB-name\fR\&. .TP \fB@code@\fR To be replaced with the generated Tcl code\&. .RE .IP The following configuration variables are special, in that they will occur within the generated code, and are replaced there as well\&. .RS .TP \fB@runtime@\fR To be replaced with the value of the configuration variable \fBruntime-command\fR\&. .TP \fB@self@\fR To be replaced with the value of the configuration variable \fBself-command\fR\&. .TP \fB@def@\fR To be replaced with the value of the configuration variable \fBproc-command\fR\&. .TP \fB@ns@\fR To be replaced with the value of the configuration variable \fBnamespace\fR\&. .TP \fB@main@\fR To be replaced with the value of the configuration variable \fBmain\fR\&. .TP \fB@prelude@\fR To be replaced with the value of the configuration variable \fBprelude\fR\&. .RE .TP \fB-name\fR string The value of this configuration variable is the name of the grammar for which the conversion is run\&. The default value is \fBa_pe_grammar\fR\&. .TP \fB-user\fR string The value of this configuration variable is the name of the user for which the conversion is run\&. The default value is \fBunknown\fR\&. .TP \fB-file\fR string The value of this configuration variable is the name of the file or other entity from which the grammar came, for which the conversion is run\&. The default value is \fBunknown\fR\&. .TP \fB-runtime-command\fR string A Tcl string representing the Tcl command or reference to it used to call PARAM instruction from parser procedures, per the chosen framework (template)\&. The default value is the empty string\&. .TP \fB-self-command\fR string A Tcl string representing the Tcl command or reference to it used to call the parser procedures (methods \&.\&.\&.) from another parser procedure, per the chosen framework (template)\&. The default value is the empty string\&. .TP \fB-proc-command\fR string The name of the Tcl command used to define procedures (methods \&.\&.\&.), per the chosen framework (template)\&. The default value is \fBproc\fR\&. .TP \fB-namespace\fR string The name of the namespace the parser procedures (methods, \&.\&.\&.) shall reside in, including the trailing '::' needed to separate it from the actual procedure name\&. The default value is \fB::\fR\&. .TP \fB-main\fR string The name of the main procedure (method, \&.\&.\&.) to be called by the chosen framework (template) to start parsing input\&. The default value is \fB__main\fR\&. .TP \fB-prelude\fR string A snippet of code to be insert at the head of each generated parsing command\&. The default value is the empty string\&. .TP \fB-indent\fR integer The number of characters to indent each line of the generated code by\&. The default value is \fB0\fR\&. .PP While the high parameterizability of this converter, as shown by the multitude of options it supports, is an advantage to the advanced user, allowing her to customize the output of the converter as needed, a novice user will likely not see the forest for the trees\&. .PP To help these latter users two adjunct packages are provided, each containing a canned configuration which will generate immediately useful full parsers\&. These are .TP \fBpt::tclparam::configuration::snit\fR Generated parsers are classes based on the \fBsnit\fR package, i\&.e\&. snit::type's\&. .TP \fBpt::tclparam::configuration::tcloo\fR Generated parsers are classes based on the \fBOO\fR package\&. .PP .SH "TCL/PARAM CODE REPRESENTATION OF PARSING EXPRESSION GRAMMARS" The Tcl/PARAM representation of parsing expression grammars is Tcl code whose execution will parse input per the grammar\&. The code is based on the virtual machine documented in the \fIPackRat Machine Specification\fR, using its instructions and a few more to handle control flow\&. .PP Note that the generated code by itself is not functional\&. It expects to be embedded into a framework which provides services like the PARAM state, implementations for the PARAM instructions, etc\&. The bulk of such a framework has to be specified through the option \fB-template\fR\&. The additional options .TP \fB-indent\fR integer .TP \fB-main\fR string .TP \fB-namespace\fR string .TP \fB-prelude\fR string .TP \fB-proc-command\fR string .TP \fB-runtime-command\fR string .TP \fB-self-command\fR string .PP provide code snippets which help to glue framework and generated code together\&. Their placeholders are in the \fIgenerated\fR code\&. .SH "PEG SERIALIZATION FORMAT" Here we specify the format used by the Parser Tools to serialize Parsing Expression Grammars as immutable values for transport, comparison, etc\&. .PP We distinguish between \fIregular\fR and \fIcanonical\fR serializations\&. While a PEG may have more than one regular serialization only exactly one of them will be \fIcanonical\fR\&. .TP regular serialization .RS .IP [1] The serialization of any PEG is a nested Tcl dictionary\&. .IP [2] This dictionary holds a single key, \fBpt::grammar::peg\fR, and its value\&. This value holds the contents of the grammar\&. .IP [3] The contents of the grammar are a Tcl dictionary holding the set of nonterminal symbols and the starting expression\&. The relevant keys and their values are .RS .TP \fBrules\fR The value is a Tcl dictionary whose keys are the names of the nonterminal symbols known to the grammar\&. .RS .IP [1] Each nonterminal symbol may occur only once\&. .IP [2] The empty string is not a legal nonterminal symbol\&. .IP [3] The value for each symbol is a Tcl dictionary itself\&. The relevant keys and their values in this dictionary are .RS .TP \fBis\fR The value is the serialization of the parsing expression describing the symbols sentennial structure, as specified in the section \fBPE serialization format\fR\&. .TP \fBmode\fR The value can be one of three values specifying how a parser should handle the semantic value produced by the symbol\&. .RS .TP \fBvalue\fR The semantic value of the nonterminal symbol is an abstract syntax tree consisting of a single node node for the nonterminal itself, which has the ASTs of the symbol's right hand side as its children\&. .TP \fBleaf\fR The semantic value of the nonterminal symbol is an abstract syntax tree consisting of a single node node for the nonterminal, without any children\&. Any ASTs generated by the symbol's right hand side are discarded\&. .TP \fBvoid\fR The nonterminal has no semantic value\&. Any ASTs generated by the symbol's right hand side are discarded (as well)\&. .RE .RE .RE .TP \fBstart\fR The value is the serialization of the start parsing expression of the grammar, as specified in the section \fBPE serialization format\fR\&. .RE .IP [4] The terminal symbols of the grammar are specified implicitly as the set of all terminal symbols used in the start expression and on the RHS of the grammar rules\&. .RE .TP canonical serialization The canonical serialization of a grammar has the format as specified in the previous item, and then additionally satisfies the constraints below, which make it unique among all the possible serializations of this grammar\&. .RS .IP [1] The keys found in all the nested Tcl dictionaries are sorted in ascending dictionary order, as generated by Tcl's builtin command \fBlsort -increasing -dict\fR\&. .IP [2] The string representation of the value is the canonical representation of a Tcl dictionary\&. I\&.e\&. it does not contain superfluous whitespace\&. .RE .PP .SS EXAMPLE Assuming the following PEG for simple mathematical expressions .PP .CS PEG calculator (Expression) Digit <- '0'/'1'/'2'/'3'/'4'/'5'/'6'/'7'/'8'/'9' ; Sign <- '-' / '+' ; Number <- Sign? Digit+ ; Expression <- Term (AddOp Term)* ; MulOp <- '*' / '/' ; Term <- Factor (MulOp Factor)* ; AddOp <- '+'/'-' ; Factor <- '(' Expression ')' / Number ; END; .CE .PP then its canonical serialization (except for whitespace) is .PP .CS pt::grammar::peg { rules { AddOp {is {/ {t -} {t +}} mode value} Digit {is {/ {t 0} {t 1} {t 2} {t 3} {t 4} {t 5} {t 6} {t 7} {t 8} {t 9}} mode value} Expression {is {x {n Term} {* {x {n AddOp} {n Term}}}} mode value} Factor {is {/ {x {t (} {n Expression} {t )}} {n Number}} mode value} MulOp {is {/ {t *} {t /}} mode value} Number {is {x {? {n Sign}} {+ {n Digit}}} mode value} Sign {is {/ {t -} {t +}} mode value} Term {is {x {n Factor} {* {x {n MulOp} {n Factor}}}} mode value} } start {n Expression} } .CE .PP .SH "PE SERIALIZATION FORMAT" Here we specify the format used by the Parser Tools to serialize Parsing Expressions as immutable values for transport, comparison, etc\&. .PP We distinguish between \fIregular\fR and \fIcanonical\fR serializations\&. While a parsing expression may have more than one regular serialization only exactly one of them will be \fIcanonical\fR\&. .TP Regular serialization .RS .TP \fBAtomic Parsing Expressions\fR .RS .IP [1] The string \fBepsilon\fR is an atomic parsing expression\&. It matches the empty string\&. .IP [2] The string \fBdot\fR is an atomic parsing expression\&. It matches any character\&. .IP [3] The string \fBalnum\fR is an atomic parsing expression\&. It matches any Unicode alphabet or digit character\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [4] The string \fBalpha\fR is an atomic parsing expression\&. It matches any Unicode alphabet character\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [5] The string \fBascii\fR is an atomic parsing expression\&. It matches any Unicode character below U0080\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [6] The string \fBcontrol\fR is an atomic parsing expression\&. It matches any Unicode control character\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [7] The string \fBdigit\fR is an atomic parsing expression\&. It matches any Unicode digit character\&. Note that this includes characters outside of the [0\&.\&.9] range\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [8] The string \fBgraph\fR is an atomic parsing expression\&. It matches any Unicode printing character, except for space\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [9] The string \fBlower\fR is an atomic parsing expression\&. It matches any Unicode lower-case alphabet character\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [10] The string \fBprint\fR is an atomic parsing expression\&. It matches any Unicode printing character, including space\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [11] The string \fBpunct\fR is an atomic parsing expression\&. It matches any Unicode punctuation character\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [12] The string \fBspace\fR is an atomic parsing expression\&. It matches any Unicode space character\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [13] The string \fBupper\fR is an atomic parsing expression\&. It matches any Unicode upper-case alphabet character\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [14] The string \fBwordchar\fR is an atomic parsing expression\&. It matches any Unicode word character\&. This is any alphanumeric character (see alnum), and any connector punctuation characters (e\&.g\&. underscore)\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [15] The string \fBxdigit\fR is an atomic parsing expression\&. It matches any hexadecimal digit character\&. This is a custom extension of PEs based on Tcl's builtin command \fBstring is\fR\&. .IP [16] The string \fBddigit\fR is an atomic parsing expression\&. It matches any decimal digit character\&. This is a custom extension of PEs based on Tcl's builtin command \fBregexp\fR\&. .IP [17] The expression [list t \fBx\fR] is an atomic parsing expression\&. It matches the terminal string \fBx\fR\&. .IP [18] The expression [list n \fBA\fR] is an atomic parsing expression\&. It matches the nonterminal \fBA\fR\&. .RE .TP \fBCombined Parsing Expressions\fR .RS .IP [1] For parsing expressions \fBe1\fR, \fBe2\fR, \&.\&.\&. the result of [list / \fBe1\fR \fBe2\fR \&.\&.\&. ] is a parsing expression as well\&. This is the \fIordered choice\fR, aka \fIprioritized choice\fR\&. .IP [2] For parsing expressions \fBe1\fR, \fBe2\fR, \&.\&.\&. the result of [list x \fBe1\fR \fBe2\fR \&.\&.\&. ] is a parsing expression as well\&. This is the \fIsequence\fR\&. .IP [3] For a parsing expression \fBe\fR the result of [list * \fBe\fR] is a parsing expression as well\&. This is the \fIkleene closure\fR, describing zero or more repetitions\&. .IP [4] For a parsing expression \fBe\fR the result of [list + \fBe\fR] is a parsing expression as well\&. This is the \fIpositive kleene closure\fR, describing one or more repetitions\&. .IP [5] For a parsing expression \fBe\fR the result of [list & \fBe\fR] is a parsing expression as well\&. This is the \fIand lookahead predicate\fR\&. .IP [6] For a parsing expression \fBe\fR the result of [list ! \fBe\fR] is a parsing expression as well\&. This is the \fInot lookahead predicate\fR\&. .IP [7] For a parsing expression \fBe\fR the result of [list ? \fBe\fR] is a parsing expression as well\&. This is the \fIoptional input\fR\&. .RE .RE .TP Canonical serialization The canonical serialization of a parsing expression has the format as specified in the previous item, and then additionally satisfies the constraints below, which make it unique among all the possible serializations of this parsing expression\&. .RS .IP [1] The string representation of the value is the canonical representation of a pure Tcl list\&. I\&.e\&. it does not contain superfluous whitespace\&. .IP [2] Terminals are \fInot\fR encoded as ranges (where start and end of the range are identical)\&. .RE .PP .PP .SS EXAMPLE Assuming the parsing expression shown on the right-hand side of the rule .PP .CS Expression <- Term (AddOp Term)* .CE .PP then its canonical serialization (except for whitespace) is .PP .CS {x {n Term} {* {x {n AddOp} {n Term}}}} .CE .PP .SH "BUGS, IDEAS, FEEDBACK" This document, and the package it describes, will undoubtedly contain bugs and other problems\&. Please report such in the category \fIpt\fR of the \fITcllib Trackers\fR [http://core\&.tcl\&.tk/tcllib/reportlist]\&. Please also report any ideas for enhancements you may have for either package and/or documentation\&. .PP When proposing code changes, please provide \fIunified diffs\fR, i\&.e the output of \fBdiff -u\fR\&. .PP Note further that \fIattachments\fR are strongly preferred over inlined patches\&. Attachments can be made by going to the \fBEdit\fR form of the ticket immediately after its creation, and then using the left-most button in the secondary navigation bar\&. .SH KEYWORDS EBNF, LL(k), PEG, TCLPARAM, TDPL, context-free languages, conversion, expression, format conversion, grammar, matching, parser, parsing expression, parsing expression grammar, push down automaton, recursive descent, serialization, state, top-down parsing languages, transducer .SH CATEGORY Parsing and Grammars .SH COPYRIGHT .nf Copyright (c) 2009 Andreas Kupries .fi