Update parser documentation

[Shushe] / README.markdown

diff --git a/README.markdown b/README.markdown
index cae7ac1a82b71159967ea3e76f2fdcc5c14d2449..885fe751dcd580ec353e52d2c1162f2eab7df1bd 100644 (file)
--- a/README.markdown
+++ b/README.markdown
@@ -1,6 +1,6 @@
 # ⛩️📰 书社
 
 # ⛩️📰 书社
 

-<b>An X·S·L·T‐based static site generator.</b>
+<b>A make·file for X·M·L.</b>

 
 <dfn>⛩️📰 书社</dfn> aims to make it easy to generate websites with
   X·S·L·T and G·N·U Make.
 
 <dfn>⛩️📰 书社</dfn> aims to make it easy to generate websites with
   X·S·L·T and G·N·U Make.


@@ -18,6 +18,15 @@ It makes things easier by :⁠—
 
 It aims to do this with zero dependencies beyond the programs already
   installed on your computer.
 
 It aims to do this with zero dependencies beyond the programs already
   installed on your computer.

+(On Linux machines, you may need to install `libxml2-utils` to get the
+  commandline programs from `libxml2`.)
+
+**Note:**
+⛩️📰 书社 requires functionality present in G·N·U Make 3.81 (or later)
+  and will not work in previous versions, or other implementations of
+  Make.
+Compatibility with later versions of G·N·U Make is assumed, but not
+  tested.

 
 ## Nomenclature
 
 
 ## Nomenclature
 


@@ -91,14 +100,19 @@ In every case, you may supply your own implementation by overriding the
   corresponding (allcaps) variable (e·g, set `MKDIR` to supply your own
   `mkdir` implementation).
 
   corresponding (allcaps) variable (e·g, set `MKDIR` to supply your own
   `mkdir` implementation).
 

+- `awk`

 - `cat`
 - `cat`

+- `cksum`

 - `cp`
 - `date`
 - `echo`
 - `file`
 - `find`
 - `cp`
 - `date`
 - `echo`
 - `file`
 - `find`

+- `git` (optional; set `GIT=` to disable)
+- `ln`

 - `mkdir` (requires support for `-p`)
 - `mv`
 - `mkdir` (requires support for `-p`)
 - `mv`

+- `od` (requires support for `-t x1`)

 - `printf`
 - `rm`
 - `sed`
 - `printf`
 - `rm`
 - `sed`


@@ -108,6 +122,7 @@ In every case, you may supply your own implementation by overriding the
 - `touch`
 - `tr` (requires support for `-d`)
 - `uuencode` (requires support for `-m` and `-r`)
 - `touch`
 - `tr` (requires support for `-d`)
 - `uuencode` (requires support for `-m` and `-r`)

+- `xargs` (requires support for `-0`)

 - `xmlcatalog` (provided by `libxml2`)
 - `xmllint` (provided by `libxml2`)
 - `xsltproc` (provided by `libxslt`)
 - `xmlcatalog` (provided by `libxml2`)
 - `xmllint` (provided by `libxml2`)
 - `xsltproc` (provided by `libxslt`)


@@ -117,10 +132,14 @@ The following additional variables can be used to control the behaviour
 
 - **`SRCDIR`:**
   The location of the source files (default: `sources`).
 
 - **`SRCDIR`:**
   The location of the source files (default: `sources`).

+  Multiple source directories can be provided, so long as the same
+    file subpath doesn’t exist in more than one of them.

 
 - **`INCLUDEDIR`:**
 
 - **`INCLUDEDIR`:**

-  The location of the source files (default: `sources/includes`).
+  The location of source includes (default: `sources/includes`).

   This can be inside of `SRCDIR`, but needn’t be.
   This can be inside of `SRCDIR`, but needn’t be.

+  Multiple include directories can be provided, so long as the same
+    file subpath doesn’t exist in more than one of them.

 
 - **`BUILDDIR`:**
   The location of the (temporary) build directory (default: `build`).
 
 - **`BUILDDIR`:**
   The location of the (temporary) build directory (default: `build`).


@@ -147,37 +166,65 @@ The following additional variables can be used to control the behaviour
   This variable is used to find the ⛩️📰 书社 `lib/` folder, which is
     expected to be in the same location.
 
   This variable is used to find the ⛩️📰 书社 `lib/` folder, which is
     expected to be in the same location.
 

-- **`MAGICDIR`:**
-  The location of the magic files to use (default: `$(THISDIR)/magic`).
+- **`MAGIC`:**
+  A white·space‐separated list of magic files to use (default:
+    `$(THISDIR)/magic/*`).

 
 

-- **`FINDOPTS`:**
-  Options to pass to `find` when searching for source files (default:
-    `-PE`).
+- **`EXTRAMAGIC`:**
+  The value of this variable is appended to `MAGIC` by default, to
+    enable additional magic files without overriding the existing ones.

 
 - **`FINDRULES`:**
 
 - **`FINDRULES`:**

-  Rules to use with `find` when searching for source files (default:
-    `-flags -nohidden -and -not -name '.*'`).
+  Rules to use with `find` when searching for source files.
+  The default ignores files that start with a period or hyphen‐minus,
+    those which end with a cloparen, and those which contain a hash,
+    buck, percent, asterisk, colon, semi, eroteme, bracket, backslash,
+    or pipe.

 
 

-- **`FINDINCLUDEOPTS`:**
-  Options to pass to `find` when searching for includes (default:
-    `$(FINDOPTS)`).
+- **`EXTRAFINDRULES`:**
+  The value of this variable is appended to `FINDRULES` by default, to
+    enable additional rules without overriding the existing ones.

 
 - **`FINDINCLUDERULES`:**
   Rules to use with `find` when searching for includes (default:
     `$(FINDRULES)`).
 
 
 - **`FINDINCLUDERULES`:**
   Rules to use with `find` when searching for includes (default:
     `$(FINDRULES)`).
 

+- **`EXTRAFINDINCLUDERULES`:**
+  The value of this variable is appended to `FINDINCLUDERULES` by
+    default, to enable additional rules without overriding the existing
+    ones.
+

 - **`PARSERS`:**
   A white·space‐separated list of parsers to use (default:
     `$(THISDIR)/parsers/*.xslt`).
 
 - **`PARSERS`:**
   A white·space‐separated list of parsers to use (default:
     `$(THISDIR)/parsers/*.xslt`).
 

+- **`EXTRAPARSERS`:**
+  The value of this variable is appended to `PARSERS` by default, to
+    enable additional parsers without overriding the existing ones.
+

 - **`TRANSFORMS`:**
   A white·space‐separated list of transforms to use (default:
     `$(THISDIR)/transforms/*.xslt`).
 
 - **`TRANSFORMS`:**
   A white·space‐separated list of transforms to use (default:
     `$(THISDIR)/transforms/*.xslt`).
 

+- **`EXTRATRANSFORMS`:**
+  The value of this variable is appended to `TRANSFORMS` by default, to
+    enable additional transforms without overriding the existing ones.
+

 - **`XMLTYPES`:**
   A white·space‐separated list of media types to consider X·M·L
     (default: `application/xml text/xml`).
 
 - **`XMLTYPES`:**
   A white·space‐separated list of media types to consider X·M·L
     (default: `application/xml text/xml`).
 

+- **`GENERATOR`:**
+  The name of the generator program (default: `⛩️📰 书社`).
+
+- **`VERSION`:**
+  The current version of `GENERATOR` (default: derived from the current
+    git tag/branch/commit).
+
+- **`SRCREV`:**
+  The current version of the source files (default: derived from the
+    current git tag/branch/commit).
+

 - **`VERBOSE`:**
   If this variable has a value, every recipe instruction will be
     printed when it runs (default: empty).
 - **`VERBOSE`:**
   If this variable has a value, every recipe instruction will be
     printed when it runs (default: empty).


@@ -206,11 +253,16 @@ Text formats with associated X·S·L·T parsers are wrapped in a H·T·M·L
 Source files whose media type does not have an associated X·S·L·T
   parser are considered “assets” and will not be transformed.
 
 Source files whose media type does not have an associated X·S·L·T
   parser are considered “assets” and will not be transformed.
 

-For compatibility with this program, source filenames should not
-  contain Ascii whitespace or any of the following Ascii characters:
-  ``!"#$%&()-:<>?\^`{|}``.
-These characters are either invalid in u·r·i’s or conflict with aspects
-  of the Make or commandline syntax.
+**☡ For compatibility with this program, source file·names must not
+  contain Ascii white·space, colons (`:`), semis (`;`), pipes (`|`),
+  bucks (`$`), percents (`%`), hashes (`#`), asterisks (`*`), brackets
+  (`[` or `]`), erotemes (`?`), backslashes (`\`), or control
+  characters, must not begin with a hyphen‐minus (`-`), and must not
+  end with a cloparen (`)`).**
+The former characters have the potential to conflict with make syntax,
+  a leading hyphen‐minus is confusable for a command‐line argument, and
+  a trailing cloparen [activates a bug in G·N·U Make
+  3.81](https://stackoverflow.com/questions/17148468/capturing-filenames-including-parentheses-with-gnu-makes-wildcard-function#comment24825307_17148894).

 
 ## Parsers
 
 
 ## Parsers
 


@@ -220,16 +272,15 @@ Parsers are used to convert plaintext files into X·M·L trees, as well
 ⛩️📰 书社 comes with some parsers; namely :⁠—
 
 - **`parsers/plain.xslt`:**
 ⛩️📰 书社 comes with some parsers; namely :⁠—
 
 - **`parsers/plain.xslt`:**

-  Wraps `text/plain` contents in a `<html:pre class="plain">` element.
+  Wraps `text/plain` contents in a `<html:pre>` element.

 
 - **`parsers/record-jar.xslt`:**
 
 - **`parsers/record-jar.xslt`:**

-  Converts `text/record-jar` contents into a
-    `<html:div class="record-jar">` of `<html:dl>` elements (one for
-    each record).
+  Converts `text/record-jar` contents into a `<html:div>` of
+    `<html:dl>` elements (one for each record).

 
 - **`parsers/tsv.xslt`:**
 
 - **`parsers/tsv.xslt`:**

-  Converts `text/tab-separated-values` contents into an
-    `<html:table class="tsv">` element.
+  Converts `text/tab-separated-values` contents into an `<html:table>`
+    element.

 
 New ⛩️📰 书社 parsers which target plaintext formats should have an
   `<xslt:template>` element with no `@name` or `@mode` and whose
 
 New ⛩️📰 书社 parsers which target plaintext formats should have an
   `<xslt:template>` element with no `@name` or `@mode` and whose


@@ -253,8 +304,10 @@ For example, the trivial `text/plain` parser is defined as follows :⁠—
 <transform
   xmlns="http://www.w3.org/1999/XSL/Transform"
   xmlns:html="http://www.w3.org/1999/xhtml"
 <transform
   xmlns="http://www.w3.org/1999/XSL/Transform"
   xmlns:html="http://www.w3.org/1999/xhtml"

+  xmlns:书社="urn:fdc:ladys.computer:20231231:Shu1She4"

   version="1.0"
 >
   version="1.0"
 >

+  <书社:id>example:text/plain</书社:id>

   <template match="html:script[@type='text/plain']">
     <html:pre><value-of select="."/></html:pre>
   </template>
   <template match="html:script[@type='text/plain']">
     <html:pre><value-of select="."/></html:pre>
   </template>


@@ -269,8 +322,21 @@ Alternatively, you can set the `@书社:supported-media-types` attribute
   on the root element of the parser to override media type support
   detection.
 
   on the root element of the parser to override media type support
   detection.
 

-Parsers can also target specific dialects of X·M·L, in which case they
-  operate on the same basic principles as transforms (described below).
+Even when `@书社:supported-media-types` is set, it is a requirement
+  that each parser transform any `<html:script>` elements with a
+  `@type` which matches their registered types into something else.
+Otherwise the parser will be stuck in an endless loop.
+The result tree of applying the transform to the `<html:script>`
+  element will be reparsed (in case any new `<html:script>` elements
+  were added in its subtree), and a `@书社:parsed-by` attribute will be
+  added to each toplevel element in the result.
+The value of this attribute will be the value of the `<书社:id>`
+  toplevel element in the parser.
+
+It is possible for parsers to support zero plaintext types.
+This is useful when targeting specific dialects of X·M·L; parsers in
+  this sense operate on the same basic principles as transforms
+  (described below).

 The major distinction between X·M·L parsers and transforms is where in
   the process the transformation happens:
 Parsers are applied *prior* to embedding (and can be used to generate
 The major distinction between X·M·L parsers and transforms is where in
   the process the transformation happens:
 Parsers are applied *prior* to embedding (and can be used to generate


@@ -280,6 +346,26 @@ It is **strongly recommended** that auxillary templates in parsers be
   namespaced (by `@name` or `@mode`) whenever possible, to avoid
   conflicts between parsers.
 
   namespaced (by `@name` or `@mode`) whenever possible, to avoid
   conflicts between parsers.
 

+### Attributes added during parsing
+
+⛩️📰 书社 will add a few attributes to the output of the parsing step,
+  namely :⁠—
+
+- A `@书社:cksum` attribute on toplevel result elements, giving the
+    `cksum` checksum of the corresponding source file.
+
+- For the elements which result from parsing plaintext `<html:script>`
+    elements :⁠—
+
+  - A `@书社:parsed-by` attribute, giving a space‐separated list of
+      parsers which parsed the node.
+    (Generally, this will be a list of one, but it is possible for the
+      result of a parse to be another plaintext node, which may be
+      parsed by a different parser.)
+
+  - A `@书社:media-type` attribute, giving the identified media type of
+      the plaintext node.
+

 ## Embedding
 
 Documents can be embedded in other documents using a `<书社:link>`
 ## Embedding
 
 Documents can be embedded in other documents using a `<书社:link>`


@@ -303,6 +389,15 @@ Embedding takes place after parsing but before transformation, so
   and update them accordingly; it will signal an error if the
   dependencies are recursive.
 
   and update them accordingly; it will signal an error if the
   dependencies are recursive.
 

+## Output Redirection
+
+By default, ⛩️📰 书社 installs files to the same location in `DESTDIR`
+  as they were placed in their `SRCDIR`.
+This behaviour can be customized by setting the `@书社:destination`
+  attribute on the root element, whose value can give a different path.
+This attribute is read after parsing, but before transformation (where
+  it is silently dropped).
+

 ## Transforms
 
 Transforms are used to convert X·M·L files into their final output,
 ## Transforms
 
 Transforms are used to convert X·M·L files into their final output,


@@ -348,10 +443,36 @@ The following are recommendations on effective creation of
 - Set `@exclude-result-prefixes` on the root `xslt:transform` element
     to reduce the number of declared namespaces in the final result.
 
 - Set `@exclude-result-prefixes` on the root `xslt:transform` element
     to reduce the number of declared namespaces in the final result.
 

-The params `$buildtime`, `$srctime`, and `$path` are available within
-  transforms and are initialized to the current time, the time that the
-  source file was last modified, and the path of the output file within
-  $(DESTDIR).
+## Global Params
+
+The following params are made available globally in parsers and
+  transforms :⁠—
+
+- **`BUILDTIME`:**
+  The current time.
+
+- **`CKSUM`:**
+  The checksum of the source file (⅌ `cksum`).
+
+- **`GENERATOR`:**
+  The value of the `GENERATOR` variable (if present).
+
+- **`SRCREV`:**
+  The value of the `SRCREV` variable (if present).
+
+- **`SRCTIME`:**
+  The time at which the source file was last modified.
+
+- **`VERSION`:**
+  The value of the `VERSION` variable (if present).
+
+The following params are only available in transforms :⁠—
+
+- **`CATALOG`:**
+  The path of the catalog file (within `BUILDDIR`).
+
+- **`PATH`:**
+  The path of the output file (within `DESTDIR`).

 
 ## Output Wrapping
 
 
 ## Output Wrapping
 


@@ -378,7 +499,7 @@ In addition to being called with the transform result, each of these
   modes will additionally be called with a `<xslt:include>` element
   corresponding to each transform.
 If a transform has a `<书社:id>` top‐level element whose value is an
   modes will additionally be called with a `<xslt:include>` element
   corresponding to each transform.
 If a transform has a `<书社:id>` top‐level element whose value is an

-  i·r·i, its `<xslt:import>` element will have a corresponding
+  i·r·i, its `<xslt:include>` element will have a corresponding

   `@书社:id` attribute.
 This mechanism can be used to allow transforms to insert content
   without matching any elements in the result; for example, the
   `@书社:id` attribute.
 This mechanism can be used to allow transforms to insert content
   without matching any elements in the result; for example, the


@@ -412,4 +533,4 @@ Source files are licensed under the terms of the <cite>Mozilla Public
   License, version 2.0</cite>.
 For more information, see [LICENSE](./LICENSE).
 
   License, version 2.0</cite>.
 For more information, see [LICENSE](./LICENSE).
 

-[draft-phillips-record-jar-01]: <https://datatracker.ietf.org/doc/html/draft-phillips-record-jar-01>
\ No newline at end of file
+[draft-phillips-record-jar-01]: <https://datatracker.ietf.org/doc/html/draft-phillips-record-jar-01>