This is Mixp, an XML Parser for Guile, written as an interface to James Clark’s expat library. The documentation is, of course, incomplete, and the interface is subject to change. However, it should be sufficient to get started. This documentation was last updated on 23 August 2011 and covers Mixp version 0.7.
Mixp is a Scheme interface to James Clark’s expat library1. It may be used to parse XML documents with Guile.
If you do not know expat, first have a look at the sample program
See Sample programs. Typically, you will create a parser object
parser-create, then associate one or more handlers to it
hset!, then parse the document with
The handlers work by side-effect, so unless the algorithm is pure
input/output, most likely you will also need to retrieve the state
they maintain, after the parse. See Expat interface.
If you happen to know expat already, you will find easily what you
are looking for by taking a C expat function name, removing the
XML_, using hyphens instead of capital letters to separate the
words, and searching it in the reference documentation. In most
cases, the prototype is the same, modulo the differences between C
The following sample program reads an XML file (provided with the
Mixp distribution), and displays its start and end tags. You can
launch a Guile shell from the test/ directory of the
distribution, and execute this code. Your
variable should contain the directory in which you installed Mixp
(that is, the directory which contains the mixp/ subdirectory).
(use-modules ((mixp expat) #:prefix E:) ((mixp utils) #:prefix U:)) (define (trace prefix) (lambda (name . ignored) (display prefix) (display name) (newline))) ;; Create the parser object. (let ((parser (E:parser-create))) ;; Specify handlers. (E:hset! parser `((element-start . ,(trace "start ")) (element-end . ,(trace "end ")))) ;; Parse the file. (call-with-input-file "REC-xml-19980210.xml" (lambda (port) (U:parse-data port parser))))
For more information about the Expat interface and handlers, See Expat interface.
The following sample program builds a hierarchical tree structure from an XML document which resides in a string. This tree structure should be easy to use with traditional Scheme procedures.
(use-modules ((mixp utils) #:prefix U:)) (let ((xml-doc "<foo name='Paul'><bar>Some text</bar><void/></foo>")) (call-with-input-string xml-doc U:xml->tree)) ⇒ ((element ("foo" (("name" . "Paul"))) (element ("bar" ()) (character-data "Some text")) (element ("void" ()))))
For more information about this interface, See High-level extensions.
From the Guile shell or from a Guile script, you should type the following commands before using the Mixp API:
(use-modules (mixp expat)) (use-modules (mixp utils))
Actually, you may load just
(mixp expat) if you intend to use
only the raw expat interface (see Expat interface).
(mixp utils) if you want to use the extension
procedures (see High-level extensions).
Mixp contains two Scheme modules:
(mixp expat)is the low-level interface to expat. It doesn’t stay as close as possible to the expat API, but someone who already knows expat will be able to note gross similarities.
(mixp utils)contains additional procedures that might be useful. For example, if you need to parse an XML file, you can use
(mixp expat)). This module may evolve into a higher-level interface, for example an object-based interface.
From another point of view, Mixp contains two files in a directory
mixp, which in turn lives in a directory somewhere along your
This section describes a few common tasks which may be solved with Mixp.
(mixp utils) without specifying a
parser. A default one will be created, and it will do nothing
interesting except raise errors if there is any error in the document:
(call-with-input-string "<doc><elem></elem>" parse-data)
Suppose you want to retrieve the text contained between an opening tag
and the matching closing tag. You may do that by using an
element-handler and a character-data-handler together. The following
code will retrieve the text between
an XML document:
(use-modules ((mixp expat) #:select E:) ((mixp utils) #:select U:)) (let ((parser (E:parser-create)) (in-title? #f) ; becomes #t inside the tag (title "")) ; will contain the result (define (toggle sense) (lambda (name . ignored) (and (string=? "title" name) (set! in-title? sense)))) (define (handle-character-data value) (and in-title? (set! title (string-append title value)))) (E:hset! parser `((element-start . ,(toggle #t)) (element-end . ,(toggle #f)) (character-data . ,handle-character-data))) (call-with-input-string "<doc><title>Hello</title></doc>" (lambda (port) (U:parse-data port parser))) (display title) (newline))
(use-modules ((mixp utils) #:prefix U:)) (call-with-input-file "file.xml" U:xml->tree)
The following program will read an XML document in foo.xml,
parse the DTD which may be referenced in the
declaration, and expand the entities.
(use-modules ((mixp expat) #:prefix E:) ((mixp utils) #:prefix U:)) (define (fso s . args) (apply simple-format #t s args)) ;; Create the parser object. (let ((parser (E:parser-create))) (define (xref-h context base system-id public-id) (fso "Ref to external entity: ~A.~%" system-id) (open-input-file system-id)) (E:set-param-entity-parsing parser 'XML_PARAM_ENTITY_PARSING_ALWAYS) ;; Specify callback functions. (E:hset! parser `((character-data . ,(lambda (value) (fso "Char: ~A.~%" value))) (external-entity-ref . ,xref-h))) ;; Parse the file. (call-with-input-file "foo.xml" (lambda (port) (U:parse-data port parser))))
You may want to define handlers to be called when Mixp parses the DTD and finds an element declaration or an attribute list declaration. Unfortunately, this is not possible, due to limitations in expat.
However, you may try to use the default handler (see Expat handlers). If DTD reading is enabled (see the previous item), then the default handler will be called repeatedly while reading the DTD, and will receive each time a part of the DTD. However, there is no guarantee about what part of the DTD it will receive each time. Building a representation of the DTD would be possible with the default handler, but not easy.
Please send bug reports to [TODO: BUG-TRACKER-URL]. We always appreciate feedback about Mixp, and suggestions about what could be improved in the interface.
This chapter describes the libexpat interface, i.e., the
(mixp expat) module. The interface has been modified
to be more “Schemey”; it does not correspond one-to-one with
libexpat. Notably, things are more symbolic and “condensed”.
Expat uses C
enums to operate symbolically.
(mixp expat), we use Scheme symbols directly.
Several procedures return a symbolic status, one of the set:
XML_STATUS_ERROR XML_STATUS_OK XML_STATUS_SUSPENDED
Here are all the symbolic error codes (see Doing a parse), presented without the ‘XML_ERROR_’ prefix.
;; since the beginning UNEXPECTED_STATE NONE ENTITY_DECLARED_IN_PE NO_MEMORY FEATURE_REQUIRES_XML_DTD SYNTAX CANT_CHANGE_FEATURE_ONCE_PARSING NO_ELEMENTS INVALID_TOKEN ;; added in 1.95.7 UNCLOSED_TOKEN UNBOUND_PREFIX PARTIAL_CHAR TAG_MISMATCH ;; added in 1.95.8 DUPLICATE_ATTRIBUTE UNDECLARING_PREFIX JUNK_AFTER_DOC_ELEMENT INCOMPLETE_PE PARAM_ENTITY_REF XML_DECL UNDEFINED_ENTITY TEXT_DECL RECURSIVE_ENTITY_REF PUBLICID ASYNC_ENTITY SUSPENDED BAD_CHAR_REF NOT_SUSPENDED BINARY_ENTITY_REF ABORTED ATTRIBUTE_EXTERNAL_ENTITY_REF FINISHED MISPLACED_XML_PI SUSPEND_PE UNKNOWN_ENCODING INCORRECT_ENCODING ;; added in 2.0 UNCLOSED_CDATA_SECTION RESERVED_PREFIX_XML EXTERNAL_ENTITY_HANDLING RESERVED_PREFIX_XMLNS NOT_STANDALONE RESERVED_NAMESPACE_URI
Everything revolves around the parser object. This section describes procedures to create and query such objects.
Return a new parser object. Optional arg encoding is a string specifying the encoding to use (for example, "UTF-8").
Optional arg encoding is a string specifying the encoding to use.
Second optional arg namespace-separator is a character used to
separate the namespace part from the local part (e.g.,
Note: Using this proc (instead of
parser-create) enables dispatch
#t if obj is an XML-Parser object,
Return “current” locus information for parser as a vector of four elements (all non-negative integers):
#(LINE COLUMN BYTE-COUNT BYTE-INDEX)
Optional arg stash specifies a vector to fill in rather
than constructing a new one. If an element in stash is
#f, the respective slot is skipped (it remains
You must specify a set of handlers, or callback procedures, for the parser to call when it encounters specific situations while processing its input. The handler name is a symbol. Unlike libexpat, there is one centralized procedure for setting and one for getting the set.
Set handlers for parser as specified in alist.
Valid values in alist are a procedure,
empty list) or
#f. Note, however, that no arity checks
are done on the procedures.
Return an alist representing the handler set of parser.
If a particular handler is not specified, that pair’s CDR
#f. The alist keys are as for
In the following description, the handler’s name is followed by the arguments that it will be called with. These are normally string values unless otherwise noted.
This handler is called when expat sees an element start. attributes is an alist whose keys and values are all strings.
<foo a="1" b="2"> name ⇒ "foo" attributes ⇒ (("a" . "1") ("b" . "2"))
Likewise, for element end.
</foo> name ⇒ "foo"
This handler is called for normal text (outside ‘<>’ tags). data should never be the empty string. It is encoded in UTF-8.
This handler is called for every processing instruction
<? ... ?>).
<?a b c d e f ?> target ⇒ "a" pi-data ⇒ "b c d e f " ;; Note the trailing whitespace.
This handler is called for comments (
<!-- ... -->).
<!-- This is a comment. --> comment ⇒ " This is a comment. " ;; Note the surrounding whitespace.
This handler is called for CDATA sections
<![CDATA[ ... ]]>).
default-expand specify the default
handler. The difference regards processing of internal entities.
defaultinhibits expansion of internal entities; they are passed, instead, to the handler.
default-expanddoes not inhibit their expansion; they are not passed to the handler.
The default handler is called for any characters in the XML document for which there is no applicable handler. This includes both characters that are part of markup which is of a kind that is not reported (comments, markup declarations), or characters that are part of a construct which could be reported but for which no handler has been supplied. The characters are passed exactly as they were in the XML document except that they will be encoded in UTF-8.
Line boundaries are not normalized. Note that a byte order mark character is not passed to the default handler. There are no guarantees about how characters are divided between calls to the default handler: for example, a comment might be split between multiple calls.
This handler is called for unparsed entity declarations
The entity-name, system-id and notation-name arguments
will never be
#f. The other arguments may be.
The base argument is whatever was set by
(see Expat misc).
<!ENTITY Antarctica SYSTEM 'http://www.antarctica.net' NDATA vrml> entity-name ⇒ "Antartica" system-id ⇒ "http://www.antarctica.net" public-id ⇒ #f notation-name ⇒ "vrml"
This handler is called for notation declarations (
Except notation-name, some of the args may be
The base argument is whatever was set by
(see Expat misc).
<!NOTATION vrml PUBLIC 'VRML 2'> notation-name ⇒ "vrml" system-id ⇒ #f public-id ⇒ "VRML 2"
When namespace processing is enabled (i.e., the parser was created with
parser-create-ns), these are called once for each namespace
declaration. The call to the start and end element handlers occur
between the calls to the start and end namespace declaration
handlers. prefix may be
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en"> prefix ⇒ #f uri ⇒ "http://www.w3.org/1999/xhtml"
This handler is called if the document is not standalone (it has an
external subset or a reference to a parameter entity, but does not
have ‘standalone="yes"’). If this handler returns
then processing will not continue, and the parser will return a
Some of the args may be
The base argument is whatever was set by
(see Expat misc).
This handler is called when the parser finds a reference to an
external entity in the document. For example, the
...> declaration contains an external entity reference when it
specifies an external DTD. In that case, you should also call
set-param-entity-parsing (see Expat misc), because you
probably want the parser to expand the references to entities
declared in your DTD. For an example, See How to....
The external entity reference handler should return an open port to
the external entity. For example, assuming that
refers to a relative file path, you may define the handler as follows:
(lambda (context base system-id public-id) (open-input-file system-id))
The system identifier (system-id) is defined by the XML specification as a URI. Therefore, the example above will only work if you know that the system id is actually a filename. You may need to use, for example, some kind of http client library if you want to support URIs which start with ‘http://’.
Note that the behaviour of this handler is very different in expat.
This handler is called when the parser does not recognize the
declared encoding of a document.
It should use
make-xml-encoding (see Expat misc),
if it thinks that it can teach the parser to decode name.
NB: Unknown encoding handlers have not been really tested, so they probably don’t work for now.
Expat supports the following encodings: UTF-8, UTF-16, ISO-8859-1, US-ASCII.
The encoding is usually indicated in the first line of an XML file
<?xml... ?> declaration). But every data you will receive
in your handlers (tag names, attributes, character data...), will be
encoded in UTF-8, whatever the original encoding was. UTF-8
represents ASCII characters with no modification, but represents other
characters with multi-byte characters. ISO-8859-1 has a better
support in standard editors, but is too euro-centric.
The encoding features of expat are not completely supported in Mixp.
Using unknown encoding handlers will not work, or at least I have not
tested that feature. However, XML documents which encoding (as
specified in the
<?xml... ?> declaration) is supported by expat
should be parsed correctly. For example, you should get an error if
you parse a document which claims to be US-ASCII but contains 8-bit
Declare that parser is the default current parser.
Set base for parser to base. Return a symbolic status.
Return the base (a string) of parser.
If none is set, return
Get the specified attribute count for parser.
Set entity parsing for parser to code (a symbol). This controls parsing of parameter entities (including the external DTD subset). See xmlparse.h for a complete description.
Return a new XML-Encoding object.
map is a vector of length 256. Each element is an integer specifying how many bytes are required to decode a multibyte “character” whose first byte is that element’s index.
convert is a proc that takes one arg, a unibyte string. It should return the "Unicode scalar value" of the string, or -1 if the byte sequence is malformed.
release is a thunk the parser calls when done all conversion work.
After all the set up (see Expat handlers), you will want to apply the parser to some input. This section describes two procedures to do that, as well as two procedures to help you understand things better when All Does Not Go Well.
Use parser to parse string s.
Optional third arg finalp, if non-
this call is the last parsing to be done on s.
Return a symbolic status.
Use parser to parse len bytes of the internal buffer.
Optional third arg finalp, if non-
means this call is the last parsing to be done.
Return a symbolic status.
Return a symbol corresponding to the error code for parser.
Return a string representing the error code (a symbol).
If code is not recognized, return
Here is an example that uses the latter two procedures. See Symbols.
(define BAD-XML "<doc>dfssfd</do>") ;; NB: not same! ^^^ ^^ (use-modules ((mixp expat) #:prefix E:)) (define PARSER (E:parser-create)) (define RES (E:parse PARSER BAD-XML #t)) RES ⇒ XML_STATUS_ERROR (define ERR (E:error-symbol PARSER)) ERR ⇒ XML_ERROR_TAG_MISMATCH (E:error-string ERR) ⇒ "mismatched tag"
The following functions are part of the expat interface, but are not exposed to Scheme.
The header file expat.h says that using this function
“is equivalent to supplying an encoding argument to
and “Note: Calling
XML_ParseBuffer has no
effect and returns
Thus, you can achieve the same effect in Mixp by specifying the encoding on parser creation (see Parser).
There is actually no good reason not to include stop/resume functionality. So, these are noted here as a “to do” item. (Patches welcome!)
This kind of integratin awaits widespread (and stable) Guile “array leasing” facilities.
This chapter describes the
(mixp utils) module,
which provides high-level extensions to the raw expat interface.
Read all bytes from port (until it yields the EOF object), and throw an error if the input does not represent a valid XML document.
Convert the byte list from from UTF-8 to Latin-1. Throw
invalid-utf8 if from is not a valid UTF-8 stream, and
no-latin1 if one of the characters is a multi-byte character
(and thus cannot be a Latin-1 character). If from is a string,
return a string. If from is a list, return a list.
Convert a UTF-8 string, such as those returned by the parser, to a
UCS-2 list. from may be a string or a list. Return a
list whose elements are sub-lists with length two, each encoding a
character from the original stream. Throw a
no-ucs2 error if
one of the characters decoded from the UTF-8 string is not a UCS-2
Convert a UTF-8 string, such as those returned by the parser, to a UCS-4 stream. from may be a string or a list. Return a list whose elements are sub-lists with length four, each encoding a character from the original stream.
Build a tree data structure from the XML document read from
port. Each XML element produces a new branch in the tree.
Optional arg parser specifies another parser to use.
The internal parser uses element start (and end),
comment handlers. (TODO: Add other handlers.)
For example, consider this sample XML document:
<foo name='Paul'><bar>Some text</bar><void/></foo>
Here is the data structure produced by
(element ("foo" (("name" . "Paul"))) (element ("bar" ()) (character-data "Some text")) (element ("void" ())))
SXML over SSAX is the usual way to go about things, but we don’t
mind being unusual on occasion. This chapter describes the
(mixp simit) module, which provides “SXML over Expat”,
more or less. (The level of imitation is low while we figure
out what the heck is going on. Later, things should align more,
and weasel words like “SXML-ish” should go away…)
Parse an XML document from port with some namespaces,
a list of elements each of the form
where nick is a symbol, and uri is a string.
The XML namespace is built-in:
If parsing is successful, return an SXML-ish tree.
parse-error with two args, the symbolic
reason (suitable for passing to
the location of the error as returned by
Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc. http://fsf.org/ Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.
This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.
We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.
This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.
A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.
A “Secondary Section” is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document’s overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.
The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.
The “Cover Texts” are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.
A “Transparent” copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not “Transparent” is called “Opaque”.
Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. Examples of transparent image formats include PNG, XCF and JPG. Opaque formats include proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML, PostScript or PDF produced by some word processors for output purposes only.
The “Title Page” means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, “Title Page” means the text near the most prominent appearance of the work’s title, preceding the beginning of the body of the text.
The “publisher” means any person or entity that distributes copies of the Document to the public.
A section “Entitled XYZ” means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. (Here XYZ stands for a specific section name mentioned below, such as “Acknowledgements”, “Dedications”, “Endorsements”, or “History”.) To “Preserve the Title” of such a section when you modify the Document means that it remains a section “Entitled XYZ” according to this definition.
The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.
You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.
You may also lend copies, under the same conditions stated above, and you may publicly display copies.
If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.
If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.
If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.
It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.
You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:
If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.
You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.
You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.
The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.
You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.
The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.
In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”
You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.
A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.
Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.
If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.
You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.
The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.
“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.
“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.
“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.
An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.
To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
Copyright (C) year your name. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''.
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:
with the Invariant Sections being list their titles, with the Front-Cover Texts being list, and with the Back-Cover Texts being list.
If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.
|Jump to:||C D E F G H L M N P R S U X|
|error code, symbolic:||Symbols|
|Doing a parse|
|Doing a parse|
|leftovers, libexpat:||Not implemented|
|libexpat leftovers:||Not implemented|
|loading Mixp:||Loading Mixp|
|miscellaneous procedures, ||Expat misc|
|mixp components:||Mixp components|
|Doing a parse|
|Doing a parse|
|parser, application to input:||Doing a parse|
|sample programs:||Sample programs|
|symbolic error code:||Symbols|
|Jump to:||C D E F G H L M N P R S U X|