Improve default parser/transform i·d’s

[Shushe] / README.markdown

diff --git a/README.markdown b/README.markdown
index 89dfd2efddc97526a4dbb4448ffff77f1a82dd94..4427c7fed710eb40a5051e147688b77e1f843478 100644 (file)
--- a/README.markdown
+++ b/README.markdown
@@ -91,6 +91,7 @@ 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).
 
+- `awk`
 - `cat`
 - `cp`
 - `date`
@@ -99,6 +100,7 @@ In every case, you may supply your own implementation by overriding the
 - `find`
 - `mkdir` (requires support for `-p`)
 - `mv`
+- `od` (requires support for `-t x1`)
 - `printf`
 - `rm`
 - `sed`
@@ -108,6 +110,7 @@ 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`)
+- `xargs` (requires support for `-0`)
 - `xmlcatalog` (provided by `libxml2`)
 - `xmllint` (provided by `libxml2`)
 - `xsltproc` (provided by `libxslt`)
@@ -154,17 +157,11 @@ The following additional variables can be used to control the behaviour
 - **`MAGICDIR`:**
   The location of the magic files to use (default: `$(THISDIR)/magic`).
 
-- **`FINDOPTS`:**
-  Options to pass to `find` when searching for source files (default:
-    `-PE`).
-
 - **`FINDRULES`:**
-  Rules to use with `find` when searching for source files (default:
-    `-flags -nohidden -and -not -name '.*'`).
-
-- **`FINDINCLUDEOPTS`:**
-  Options to pass to `find` when searching for includes (default:
-    `$(FINDOPTS)`).
+  Rules to use with `find` when searching for source files.
+  The default ignores hidden files, those that start with a period or
+    hyphen‐minus, and those which contain a pipe, buck, percent, or
+    colon.
 
 - **`FINDINCLUDERULES`:**
   Rules to use with `find` when searching for includes (default:
@@ -210,11 +207,12 @@ 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.
 
-For compatibility with this program, source filenames should not
-  contain Ascii whitespace or any of the following Ascii characters:
-  ``!"#$%&()-:<>?\^`{|}``.
-These characters are either invalid in u·r·i’s or conflict with aspects
-  of the Make or commandline syntax.
+**☡ For compatibility with this program, source filenames must not
+  contain Ascii whitespace, colons (`:`), pipes (`|`), bucks (`$`),
+  percents (`%`) or control characters, and must not begin with a
+  hyphen‐minus (`-`).**
+The former characters have the potential to conflict with make syntax,
+  and a leading hyphen‐minus is confusable for a command‐line argument.
 
 ## Parsers
 
@@ -257,8 +255,10 @@ 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"
+  xmlns:书社="urn:fdc:ladys.computer:20231231:Shu1She4"
   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>
@@ -273,8 +273,21 @@ Alternatively, you can set the `@书社:supported-media-types` attribute
   on the root element of the parser to override media type support
   detection.
 
-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
@@ -307,6 +320,15 @@ Embedding takes place after parsing but before transformation, so
   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,
@@ -382,7 +404,7 @@ 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
-  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