Add <书社:apply-attributes> transformation

[Shushe] / README.markdown

diff --git a/README.markdown b/README.markdown
index f2cfdd911a8801025f26655ab083b3b47fe374b8..cafda3aa533ebb233f4538f78ddba6e4b21f22a2 100644 (file)
--- a/README.markdown
+++ b/README.markdown
@@ -93,6 +93,7 @@ In every case, you may supply your own implementation by overriding the
 
 - `cat`
 - `cp`
+- `date`
 - `echo`
 - `file`
 - `find`
@@ -102,6 +103,7 @@ In every case, you may supply your own implementation by overriding the
 - `rm`
 - `sed`
 - `sleep`
+- `stat`
 - `test`
 - `touch`
 - `tr` (requires support for `-d`)
@@ -244,6 +246,9 @@ For example, the trivial `text/plain` parser is defined as follows :⁠—
   the set of allowed plaintext file types.
 Multiple such `<xslt:template>` elements may be provided in a single
   parser, for example if the parser supports multiple media types.
+Alternatively, you can set the `@书社:supported-media-types` attribute
+  on the root element of the parser to override media type support
+  detection.
 
 It is **strongly recommended** that all templates in parsers other than
   those described above be namespaced (by `@name` or `@mode`), to avoid
@@ -278,6 +283,14 @@ Transforms are used to convert X·M·L files into their final output,
   after all necessary parsing and embedding has taken place.
 ⛩️📰 书社 comes with some transforms; namely :⁠—
 
+- **`transforms/attributes.xslt`:**
+  Applies transforms to the children of any `<书社:apply-attributes>`
+    elements, and then applies the attributes of the
+    `<书社:apply-attributes>` to each result child, replacing the
+    element with the result.
+  This is useful in combination with image embeds to apply alt‐text to
+    the resulting `<html:img>`.
+
 - **`transforms/asset.xslt`:**
   Converts `<html:object>` elements which correspond to recognized
     media types into the appropriate H·T·M·L elements, and deletes
@@ -309,6 +322,11 @@ 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.
 
+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).
+
 ## Output Wrapping
 
 ⛩️📰 书社 will wrap the final output of the transforms in appropriate