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A fork with support for documentation of Salve, a Javascript library which implements a validator able to validate an XML document on the basis of a subset of RelaxNG.

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[![Package bagge](https://badge.fury.io/js/salve.svg)](https://badge.fury.io/js/salve) [![License badge](https://img.shields.io/badge/License-MPL%202.0-brightgreen.svg)](https://opensource.org/licenses/MPL-2.0) [![Travis badge](https://travis-ci.org/mangalam-research/salve.svg?branch=master)](https://travis-ci.org/mangalam-research/salve) [![Greenkeeper badge](https://badges.greenkeeper.io/mangalam-research/salve.svg)](https://greenkeeper.io/) Introduction ============ Salve (Schema-Aware Library for Validation and Edition) is a TypeScript library which implements a validator able to validate an XML document on the basis of a subset of Relax NG (RNG). It is developed as part of the Buddhist Translators Workbench. It can be seen in action in the VS Code extension [Scholarly XML](https://marketplace.visualstudio.com/items?itemName=raffazizzi.sxml). Salve is used for validating XML with custom Relax NG schemas. We've also validated files that use the [TEI standard](http://www.tei-c.org/) and the DocBook v5.0 schema. We want to support as much Relax NG as reasonably possible, but salve currently has the following limitations: * XML Schema types ``ENTITY`` and ``ENTITIES`` are treated as a ``string``. * None of the XML Schema types that deal with time allow the parameters ``minInclusive``, ``minExclusive``, ``maxInclusive`` and ``maxExclusive``. * Salve does not verify that numerical values validated as ``float`` or ``double`` fit within the limits of ``float`` or ``double``. (This is a common limitation of validators. We tested with ``jing`` and ``xmllint --relaxng`` and found they do not raise errors if, for instance, a validation that expects a float is given a value that cannot be represented with a float.) A full validation solution has the following components: * A tokenizer: responsible for recognizing XML tokens, tag names, tag delimiters, attribute names, attribute values, etc. * A parser: responsible for converting tokens to validation events (see below). * A well-formedness checker. Please check the [Events](#events) section for more information about what this concretely means. * A validator: responsible for checking that validation events are valid against a schema, telling the parser what is possible at the current point in validation, and telling the parser what is possible in general (e.g., what namespace uris are used in the schema). **This is what salve offers, and only this!** A good example of this division of labor can be found in ``bin/parse.js`` and in the test suite. In both cases the tokenizer function is performed by ``saxes``, and the parser function is performed by a parser object that ``saxes`` creates, customized to call salve's ``Walker.fireEvent()``. The original Salve has a sister library named [salve-dom](https://github.com/mangalam-research/salve-dom) which uses the parsing facilities available in a browser to provide the tokenizer, well-formedness and parser components described above. **NB this salve-dom may not work with this fork of salve.** NOTE: If you are looking at the source tree of salve as cloned from GitHub, know that executables cannot be executed from ``bin``. They can be executed after a build, from the ``build/dist/bin`` directory. If you are looking at the files installed by ``npm`` when you install salve as a *package*, the files in ``bin`` *are* those you want to execute. Basic Usage =========== A typical usage scenario would be as follows: // Import the validation module const salve = require("salve-annos"); // Source is a URL to the Relax NG schema to use. A ``file://`` URL // may be used to load from the local fs. const grammar = salve.convertRNGToPattern(source).pattern; // Get a walker on which to fire events. const walker = grammar.newWalker(); Then the code that parses the XML file to be validated should call ``fireEvent()`` on ``walker``. Remember to call the ``end()`` method on your walker at the end of validation to make sure that there are no unclosed tags, etc. The file ``bin/parse.js`` (included in salve's source but not in the npm module) contains an example of a rudimentary parser runnable in Node.js:: $ node ....../parse.js [rng] [xml to validate] The ``[rng]`` parameter is the Relax NG schema, recorded in the full XML format used by Relax NG (not the compact form). The ``[xml to validate]`` parameter is the XML file to validate against the schema. Converting Schemas ================== As you can see above, a Relax NG schema, stored in XML, needs to be converted to salve's internal format before salve can use it. Internally this happens: * The XML file recording the Relax NG schema is converted to a tree of objects representing the XML. * The XML tree is validated against the Relax NG schema. * The XML tree is simplified as described in the Relax NG specification. * Constraints specified by the Relax NG specification are checked. * The XML tree is converted to a "pattern", which is a structure internal to salve. The simplest usage is like this:: const result = salve.convertRNGToPattern(source); By default the conversion returns an object with a grammar stored on the ``pattern`` field, may reveal some simplification warnings on the ``warnings`` field, and provides a the simplified schema as an XML tree on the ``simplified`` field. In trivial use-case scenarios, only ``pattern`` and ``warnings`` are used. In some cases, the code using ``convertRNGToPattern`` may want to serialize the result of simplification for future use. To do this, it should use ``writeTreeToJSON`` and pass the value of the ``simplified`` field to serialize the simplified XML tree to JSON. The serialized JSON may then be read with ``readTreeFromJSON`` to create a structure identical to the original ``pattern``. Consider the following code:: const result = salve.convertRNGToPattern(source); const json = salve.writeTreeToJSON(result.simplified); const x = salve.readTreeFromJSON(json); After executing it, ``x`` contains a pattern which represents the same Relax NG schema as ``result.pattern``. Do note that that ``writeTreeToJSON`` takes **an XML tree** and produces JSON, whereas ``readTreeFromJSON`` reads a JSON and produces **a pattern** rather than an XML tree. There is currently no use-case scenario that requires the two functions to mirror one-another. Optionally, you may pass an options object as the 2nd argument of ``convertRNGToPattern`` with ``createManifest`` set to ``true``. If you do this, then you also get a ``manifest`` field which is an array of objects containing file paths and their corresponding hashes. Manifests are useful to allow systems that use salve to know whether a pattern needs to be regenerated with ``convertRNGToPattern``. This is necessary if the system allows a schema to change after use. Consider the following scenario. Alice uses an XML editor that uses salve to perform on the fly validation. 1. Alice edits the file ``foo.xml`` with the schema ``foo.rng``. It so happens that ``foo.rng`` imports ``math.rng``. The editor will use ``convertRNGToPattern`` to convert ``foo.rng`` and ``math.rng`` into the format salve needs. It also uses ``writeTreeToJSON`` to cache the result. Alice sees a brief progress indicator while the editor converts the schema. 2. Over the span of a week, Alice continues editing ``foo.xml``. Each time she opens the editor, the editor uses ``readTreeFromJSON`` to load the tree from cache instead of using ``convertRNGToPattern`` over and over. As far as Alice is concerned, the editor starts immediately. There's no progress indicator needed because ``readTreeFromJSON`` is super fast. 3. Alice then changes ``math.rng`` to add new elements. When Alice starts the XML editor to edit ``foo.xml`` again, the XML editor must be able to detect that the schema needs to go through ``convertRNGToPattern`` *again* because ``math.rng`` has changed. The manifest is used to support the scenario above. If the XML editor stores the converted schema, and the manifest into its cache, then it can detect if and when it needs to convert the schema anew. Security note: It is up to you to decide what strength hash you need. **The manifest is not designed for the sake of providing security.** So its hashes are not designed to detect willful tampering but rather to quickly determine whether a schema was edited. In the vast majority of real world usage scenarios, using a stronger hash would not provide better security because if an attacker can replace a schema with their own file, they also can access the manifest and replace the hash in the manifest. Events ====== Salve expects that the events it receives are those that would be emitted when validating a **well-formed document**. That is, passing to salve the events emitted from a document that is malformed will cause salve to behave in an undefined manner. (It may crash. It may generate misleading errors. It may not report any errors.) This situation is due to the fact that salve is currently developed in a context where the documents it validates cannot be malformed (because they are represented as DOM trees). So salve contains no functionality to handle problems with well-formedness. Salve **can be used on malformed documents**, provided you take care of reporting malformedness issues yourself and strategize how you will pass events to salve. Multiple strategies are possible for using salve in a context where well-formedness is not guaranteed. There is no one-size-fits-all solution here. A primitive parser could abort as soon as evidence surfaces that the document is malformed. A more sophisticated parser could process the problematic structure so as to generate an error but give salve something well-formed. For instance if parsing ``<foo></baz>``, such parser could emit an error on encountering ``</baz>`` and replace the event that would be emitted for ``</baz>`` with the event that would be emitted for ``</foo>``, and salve will happily validate it. The user will still get the error produced by the parser, and the parser will still be able to continue validating the document with salve. The parser is responsible for calling ``fireEvent()`` on the walker returned by the tree created from the RNG. (See above.) The events currently supported by ``fireEvent()`` are defined below: ``"enterStartTag", [uri, local-name]`` Emitted when encountering the beginning of a start tag (the string "<tag", where "tag" is the applicable tag name) or the equivalent. The qualified name should be resolved to its uri and local-name components. ``"leaveStartTag", []`` Emitted when encountering the end of a start tag (the string ">") or equivalent. ``"endTag", [uri, local-name]`` Emitted when encountering an end tag. ``"attributeName", [uri, local-name]`` Emitted when encountering an attribute name. ``"attributeValue", [value]`` Emitted when encountering an attribute value ``"text", [value]`` Emitted when encountering text. This event must be fired for all instances of text, **including white space.** Moreover, salve requires that you fire one ``text`` event per consecutive sequence of text. For instance, if you have the text ``foo bar`` you may not fire one event for ``foo `` and another for ``bar``. Or if you have a sequence of lines, you may not fire one event per line. You have to concatenate the lines and fire a single ``text`` event. Do not generate ``text`` events with an empty string as the value. (Conversely, a valid document **must** have an ``attributeValue`` for all attributes, even those that have empty text as a value.) Salve support a couple of compact events that serve to pass as one event data that would normally be passed as multiple events: ``"attributeNameAndValue", [uri, local-name, value]`` Combines the ``attributeName`` and ``attributeValue`` events into one event. ``"startTagAndAttributes", [uri, local-name, [attribute-data...]]`` Combines the ``enterStartTag``, ``attributeNameAndValue`` and ``leaveStartTag`` events. The ``attribute-data`` part of the event must be a sequence of ``uri, local-name, value`` as would be passed to with ``attributeNameAndValue``. For instance if an element named ``foo`` has the attribute ``a`` with the value ``valA``, the event would be: ``"startTagAndAttributes", "", foo, "", "a", "valA"``. .. note:: The compact events do not allow salve to be very precise with reporting errors. It is recommended to use them only when optimizing for speed, at the expense of precision. .. note:: When reporting possible events, salve *never* returns compact events in the list. The reason for the set of events supported is that salve is designed to handle **not only** XML modeled as a DOM tree but also XML parsed as a text string being dynamically edited. The best and closest example of this would be what ``nxml-mode`` does in Emacs. If the user starts a new document and types only the following into their editing buffer:: <html then what the parser has seen by the time it gets to the end of the buffer is an ``enterStartTag`` event with an empty uri and the local-name "html". The parser will not see a ``leaveStartTag`` event until the user enters the greater-than symbol ending the start tag. You must call ``enterContext()`` or ``enterContextWithMapping`` each time you encounter a start tag that defines namespaces and call ``leaveContext()`` when you encounter its corresponding end tag. You must also call ``definePrefix(...)`` for each prefix defined by the element. Example:: <p xmlns="q" xmlns:foo="foons">... would require calling:: enterContext() definePrefix("", "q") definePrefix("foo", "foons") Presumably, after the above, your code would call ``resolveName("p")`` on your walker to determine what namespace ``p`` is in, which would yield the result ``"q"``. And then it would fire the ``enterStartTag`` event with ``q`` as the namespace and ``p`` as the local name of the tag:: "enterStartTag", ["q", "p"] Note the order of the events. The new context must start before salve sees the ``enterStartTag`` event because the way namespaces work, a start tag can declare its own namespace. So by the time ``enterStartTag`` is issued, salve must know what namespaces are declared by the tag. If the events were not issued this way, then the start tag ``p`` in the example would be interpreted to be in the default namespace in effect **before** it started, which could be other than ``q``. Similarly, ``leaveContext`` must be issued after the corresponding ``endTag`` event. **Note on performance:** if you already have a simple JavaScript object that maps prefixes to URIs it is better to call ``enterContextWithMapping`` and pass your object to this method. ``enterContextWithMapping`` enters a new context and immediately initializes it with the mapping you pass. This is faster than calling ``enterContext`` and calling ``definePrefix`` a bunch of times. For the lazy: it is possible to call ``enterContext()`` for each start tag and ``leaveContext()`` for each end tag irrespective of whether or not the start tag declares new namespaces. The test suite does it this way. Note, however, that performance will be affected somewhat because name resolution will have to potentially search a deeper stack of contexts than would be strictly necessary. Support for Guided Editing ========================== Calling the ``possible()`` method on a walker will return the list of valid ``Event`` objects that could be fired on the walker, given what the walker has seen so far. If the user is editing a document which contains only the text:: <html and hits a function key which makes the editor call ``possible()``, then the editor can tell the user what attributes would be possible to add to this element. In editing facilities like ``nxml-mode`` in Emacs this is called completion. Similarly, once the start tag is ended by adding the greater-than symbol:: <html> and the user again asks for possibilities, calling ``possible()`` will return the list of ``Event`` objects that could be fired. Note here that it is the responsibility of the editor to translate what salve returns into something the user can use. The ``possible()`` function returns only ``Event`` objects. Editors that would depend on salve for guided editing would most likely need to use the ``clone()`` method on the walker to record the state of parsing at strategic points in the document being edited. This is to avoid needless reparsing. How frequently this should happen depends on the structure of the editor. The ``clone()`` method and the code it depends on has been optimized since early versions of salve, but it is possible to call it too often, resulting in a slower validation speed than could be attained with less aggressive cloning. Overbroad Possibilities ----------------------- ``possible()`` may at times report possibilities that allow for a document structure that is ultimately invalid. This could happen, for instance, where the Relax NG schema uses ``data`` to specify that the document should contain a ``positiveInteger`` between 1 and 10. The ``possible()`` method will report that a string matching the regular expression ``/^\+?\d+$/`` is possible, when in fact the number ``11`` would match the expression but be invalid. The software that uses salve should be prepared to handle such a situation. Name Classes ------------ .. note:: The symbol ``ns`` used in this section corresponds to ``uri`` elsewhere in this document and ``name`` corresponds to ``local-name`` elsewhere. We find the ``uri``, ``local-name`` pair to be clearer than ``ns``, ``name``. Is ``ns`` meant to be a namespace prefix? A URI? Is ``name`` a qualified name, a local name, something else? So for the purpose of documentation, we use ``uri``, ``local-name`` wherever we can. However, the Relax NG specification uses the ``ns``, ``name`` nomenclature, which salve also follows internally. The name class support is designed to be a close representation of what is described in the Relax NG specification. Hence the choice of nomenclature in this section. The term "name class" is defined in the Relax NG specification, please refer to the specification for details. Support for Relax NG's name classes introduces a few peculiarities in how possibilities are reported to clients using salve. The three events that accept names are affected: ``enterStartTag``, ``endTag``, and ``attributeName``. When salve returns these events as possibilities, their lone parameter is an instance of ``name_patterns.Base`` class. This object has a ``.match`` method that takes a namespace and a name and will return ``true`` if the namespace and name match the pattern, or ``false`` if not. Client code that wants to provide a sophisticated analysis of what a name class does could use the ``.toObject()`` method to get a plain JavaScript object from such an object. The returned object is essentially a syntax tree representing the name class. Each pattern has a unique structure. The possible patterns are: * ``Name``, a pattern with fields ``ns`` and ``name`` which respectively record the namespace URL and local name that this object matches. (Corresponds to the ``<name>`` element in the simplified Relax NG syntax.) * ``NameChoice``, a pattern with fields ``a`` and ``b`` which are two name classes. (Corresponds to a ``<choice>`` element appearing inside a name class in the simplified Relax NG syntax.) * ``NsName``, a pattern with the field ``ns`` which is the namespace that this object would match. The object matches any name. It may have an optional ``except`` field that contains a name class for patterns that it should not match. The lack of ``name`` field distinguishes it from ``Name``. (Corresponds to an ``<nsName>`` element in the simplified Relax NG syntax.) * ``AnyName``, a pattern. It has the ``pattern`` field set to ``AnyName``. We use this ``pattern`` field because ``AnyName`` does not require any other fields so ``{}`` would be its representation. This representation would too easily mask possible coding errors. ``AnyName`` matches any combination of namespace and name. May have an optional ``except`` field that contains a name class for patterns it should not match. It corresponds to an ``<anyName>`` element in the simplified Relax NG syntax. .. note:: We do not use the ``pattern`` field for all patterns above because the only reason to do so would be to distinguish ambiguous structures. For instance, if Relax NG were to introduce a ``<superName>`` element that also needs ``ns`` and ``name`` fields then it would look the same as ``<name>`` and we would not be able to distinguish one from the other. However, Relax NG is stable. In the unlikely event a new version of Relax NG is released, we'll cross whatever bridge needs to be crossed. Note that the ``<except>`` element from Relax NG does not have a corresponding object because the presence of ``<except>`` in a name class is recorded in the ``except`` field of the patterns above. Here are a couple of examples. The name class for:: element (foo | bar | foo:foo) { ... } would be recorded as (after partial beautification):: { a: { a: {ns: "", name: "foo"}, b: {ns: "", name: "bar"} }, b: {ns: "foo:foo", name: "foo"} } The name class for:: element * - (foo:* - foo:a) { ... } would be recorded as (after partial beautification):: { pattern: "AnyName", except: { ns: "foo:foo", except: {ns: "foo:foo", name: "a"} } } Clients may want to call the ``.simple()`` method on a name pattern to determine whether it is simple or not. A pattern is deemed "simple" if it is composed only of ``Name`` and ``NameChoice`` objects. Such a pattern could be presented to a user as a finite list of possibilities. Otherwise, if the pattern is not simple, then either the number of choices is unbounded or it not a discrete list of items. In such a case, the client code may instead present to the user a field in which to enter the name of the element or attribute to be created and validate the name against the pattern. The method ``.toArray()`` can be used to reduce a pattern which is simple to an array of ``Name`` objects. Event Asymmetry --------------- **Note that the events returned by ``possible()`` are *not identical* to the events that ``fireEvent()`` expects.** While most events returned are exactly those that would be passed to ``fireEvent()``, there are three exceptions: the ``enterStartTag``, ``endTag`` and ``attributeName`` events returned by ``possible()`` will have a single parameter after the event name which is an object of ``name_patterns.Base`` class. However, when passing a corresponding event to ``fireEvent()``, the same events take two string parameters after the event name: a namespace URL and a local name. To spell it out, they are of this form:: event_name, [uri, local-name] where ``event_name`` is the string which is the name of the event to fire, ``uri`` is the namespace URI and ``local-name`` is the local name of the element or attribute. Error Messages -------------- Error messages that report attribute or element names use the ``name_patterns.Name`` class to record names, even in cases where ``patterns.EName`` would do. This is for consistency purposes, because some error messages **must** use ``name_patterns`` objects to report their errors. Rather than have some error messages use ``EName`` and some use the object in ``name_patterns`` they all use the objects in ``name_patterns``, with the simple cases using ``name_patterns.Name``. In most cases, in order to present the end user of your application with error messages that make sense *to the user*, you will need to process error messages. This is because error messages generated by salve provide in the error object ``(ns, local name)`` pairs. A user would most likely like to see a namespace prefix rather than URI (``ns``). However, since namespace prefixes are a matter of user preference, and there may be many ways to decide how to associate a namespace prefix with a URI, salve does not take a position in this matter and lets the application that uses it decide how it wants to present URIs to users. The application also has to determine what strategy to use to present complex (i.e., non-simple) name patterns to the user. Again, there is no one-size-fits-all solution. Misplaced Elements ================== A problem occurs when validating an XML document that contains an unexpected element. In such case, salve will issue an error but then what should it do with the contents of the misplaced element? Salve handles this in two ways: 1. If the unexpected element is known in the schema and has only one definition, then salve will assume that the user meant to use the element defined in the schema and will validate it as such. 2. Otherwise, salve will turn off validation until the element is closed. Consider the following case:: <p>Here we have a <name><first>John</first><last>Doe</last></name> because the <emph>person's name</emph> is not known.</p> If ``name`` cannot appear in ``p`` but ``name`` has only one definition in the schema, then salve will emit an error upon encountering the ``enterStartTag`` event for ``name``, and then validate ``name`` as if it had been found in a valid place. If it turns out that the schema defines one ``name`` element which can appear inside a ``person`` element and another ``name`` element which can appear inside a ``location`` element (which would be possible with Relax NG), then salve will emit an error but won't perform any validation inside ``name``. Validation will resume after the ``endTag`` event for ``name``. (Future versions of salve may implement logic to figure out ambiguous cases such as this one.) This latter scenario also occurs if ``name`` is not defined at all by the schema. Documentation ============= The code is documented using ``typedoc``. The following command will generate the documentation:: $ gulp doc You may need to create a ``gulp.local`` module to tell ``gulp`` where to get ``rst2html``. (Defaults are such that ``gulp`` will use your ``PATH`` to locate such tools.) The formatted documentation will appear in the ``build/api/`` subdirectory, and the ``README.html`` in the root of the source tree. **NOTE**: All the public interfaces of salve are available through the ``validate`` module. However, ``validate`` is a facade that exposes interfaces that are implemented in separate modules like ``patterns`` and ``formats``. Dependencies ============ In Node ------- Whenever you call on salve's functionalities to read a Relax NG schema, the ``fetch`` function must be available in the global space for salve to use. On Node, this means you must load a polyfill to provide this function. Running salve's tests **additionally** requires that the development dependencies be installed. Please see the ``package.json`` file for details regarding these dependencies. Note that ``gulp`` should be installed so that its executable is in your path. Either this, or you will have to execute ``./node_modules/.bin/gulp`` If you want to contribute to salve, your code will have to pass the checks listed in ``.glerbl/repo_conf.py``. So you either have to install glerbl to get those checks done for you or run the checks through other means. See [Contributing](#contributing). In The Browser -------------- The following lists the most prominent cases. It is not practical for us to keep track of every single feature that old browsers like IE11 don't support. * ``fetch`` must be present. * ``Promise`` must be present. * ``Object.assign`` must be present. * ``URL`` must be present. * ``Symbol`` [and ``Symbol.iterator``] must be present. * The String methods introduced by ES6 (``includes``, ``endsWith``, etc.) * ``Array.prototype.includes`` * Old ``Set`` and ``Map`` implementations like those in IE11 are either broken or incomplete. On old browsers, we recommend using ``core-js`` to take care of many of these in one fell swoop. You'll have to provide polyfills for ``fetch`` and ``URL`` from other sources. Note that we do not support old browsers. Notably, salve won't run on any version of IE. Build System ============ Salve uses gulp. Salve's build setup gets the values for its configuration variables from three sources: * Internal default values. * From an optional ``gulp.local.js`` module that can override the internal defaults. * From command line options that can override everything above. The variables that can be set are: +-----------------------+------------------------------------------------------+ |Name | Meaning | +=======================+======================================================+ |``doc_private`` | Whether to produce documentation for private | | | entities. You can set ``doc_private`` to ``false`` | | | using ``no_doc_private``. | +-----------------------+------------------------------------------------------+ |``mocha_grep`` | ``--grep`` parameter for Mocha | +-----------------------+------------------------------------------------------+ |``rst2html`` | ``rst2html`` command to run | +-----------------------+------------------------------------------------------+ Note that when used on the command line, underscores become dashes, thus ``--mocha-grep`` and ``--doc-private``. The ``gulp.local.js`` file is a module. You must export values like this:: exports.doc_private = true Building ======== Run:: $ gulp This will create a ``build/dist/`` subdirectory in which the JavaScript necessary to validate XML files against a prepared Relax NG schema. You could copy what is in ``build/dist>`` to a server to serve these files to a client that would then perform validation. Deploying ========= When you install salve through `npm`, you get a package that contains: * a hierarchy of CommonJS modules in `lib`, * a minified UMD build as `salve.min.js`. The UMD build can be loaded in a CommonJS environment, in a AMD environment or as "plain scripts" in a browser. If you use the latter, then salve will be accessible as the `salve` global. Publish to NPM ========= Do not publish from the root directory. Instead do this: * Build with `npm run build` * Run `npm publish` from `build/dist` Testing ======= NB Tests are not fully up to date on this fork and will fail. Running the following command from the root of salve will run the tests:: $ gulp test Running ``mocha`` directly also works, but this may run the test against stale code, whereas ``gulp test`` always runs a build first. Contributing ============ Contributions must pass the commit checks turned on in ``glerbl/repo_conf.py``. Use ``glerbl install`` to install the hooks. Glerbl itself can be found at https://github.com/lddubeau/glerbl. It will eventually make its way to the Python package repository so that ``pip install glerbl`` will work. Schema File Format ================== ``writeTreeToJSON`` converts a Relax NG file formatted in XML into a more compact format used by salve at validation time. Salve supports version 3 of this file format. Versions 0 to 2 are now obsolete. The structure is:: {"v":<version>,"o":<options>,"d":[...]} The ``v`` field gives the version number of the data. The ``o`` field is a bit field of options indicating how the file was created. Right now the only thing it records is whether or not element paths are present in the generated file. The ``d`` field contains the actual schema. Each item in it is of the form:: [<array type>, ...] The first element, ``<array type>``, determines how to interpret the array. The array type could indicate that the array should be interpreted as an actual array or that it should be interpreted as an object of type ``Group`` or ``Choice``, etc. If it is an array, then ``<array type>`` is discarded and the rest of the array is the converted array. If it is another type of object then again the ``<array type>`` is discarded and an object is created with the rest of the array as its constructor's parameters. All the array's elements after ``<array type>`` can be JSON primitive types, or arrays to be interpreted as actual arrays or as objects as described above. License ======= Original Code ------------- Code completely original to salve is released under the [Mozilla Public License version 2.0](http://www.mozilla.org/MPL/2.0/). Copyright 2013-2016 Mangalam Research Center for Buddhist Languages, Berkeley, CA. RNG Simplification Code ----------------------- The RNG simplification files coded in XSL were adapted from [Nicolas Debeissat's code](https://github.com/ndebeiss/jsrelaxngvalidator/commit/8d353c73880ff519b31193905638cc97a93d1fad). These files were originally released under the [CeCILL license](http://www.cecill.info/index.en.html). Nicolas in [March 2016](https://github.com/ndebeiss/jsrelaxngvalidator/commit/f7336b2472baec60ab16571b865447e1146196ab) then changed the license to the Apache License 2.0. In the version of these files bundled with salve, multiple bugs have been corrected, some minor and some major, and some changes have been made for salve's own internal purposes. For the sake of simplicity, these changes are also covered by the original licenses that apply to Nicolas' code. Credits ======= This fork of Salve is maintained by Raff Viglianti. Salve is designed and developed by Louis-Dominique Dubeau, Director of Software Development for the Buddhist Translators Workbench project, Mangalam Research Center for Buddhist Languages. Jesse Bethel has contributed to salve's documentation, and migrated salve's build system from Make to Grunt. [![Mangalam Research Logo](https://secure.gravatar.com/avatar/7fc4e7a64d9f789a90057e7737e39b2a)](http://www.mangalamresearch.org/) This software has been made possible in part by a Level I Digital Humanities Start-up Grant and a Level II Digital Humanities Start-up Grant from the National Endowment for the Humanities (grant numbers HD-51383-11 and HD-51772-13). Any views, findings, conclusions, or recommendations expressed in this software do not necessarily represent those of the National Endowment for the Humanities. <img src="https://www.neh.gov/sites/default/files/inline-files/NEH-Preferred-Seal820.jpg" alt="NEH" width="250"> <!-- # LocalWords: fireEvent js chai semver json xmllint xsltproc npm # LocalWords: RNG minified rng XSLT xsl constructTree newWalker mk # LocalWords: xml enterStartTag uri leaveStartTag endTag nxml html # LocalWords: attributeName attributeValue Debeissat's API # LocalWords: CeCILL tokenizer Makefile README boolean anyName RST # LocalWords: nsName URIs uris enterContext leaveContext xmlns rst # LocalWords: definePrefix useNameResolver foons resolveName HD NG # LocalWords: args param TEI glerbl Github reStructuredText readme # LocalWords: validator namespace RequireJS subdirectory DOM cli # LocalWords: Dubeau Mangalam argparse Gruntfile Bethel unclosed # LocalWords: runnable namespaces reparsing amd executables usr lt # LocalWords: deployable schemas LocalWords api dir maxInclusive # LocalWords: minInclusive minExclusive maxExclusive cd abcd jing # LocalWords: github jison NaN baz emph lodash xregexp XRegExp ns # LocalWords: init positiveInteger NCName NameChoice superName # LocalWords: EName -->