Improve global params in parsers/transforms

[Shushe] / README.markdown

diff --git a/README.markdown b/README.markdown
index 4427c7fed710eb40a5051e147688b77e1f843478..400679f090097a8bbb2368fc438a55c6a5c57084 100644 (file)
--- a/README.markdown
+++ b/README.markdown
@@ -98,6 +98,7 @@ In every case, you may supply your own implementation by overriding the
 - `echo`
 - `file`
 - `find`
+- `git` (optional; set `GIT=` to disable)
 - `mkdir` (requires support for `-p`)
 - `mv`
 - `od` (requires support for `-t x1`)
@@ -374,10 +375,32 @@ 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
-  $(DESTDIR).
+## Global Params
+
+The following params are made available globally in parsers and
+  transforms :⁠—
+
+- **`BUILDTIME`:**
+  The current time.
+
+- **`SRCREV`:**
+  The tag or hash of the current commit in the working directory (if
+    `GIT` is defined and `./.git` exists).
+
+- **`SRCTIME`:**
+  The time at which the source file was last modified.
+
+- **`VERSION`:**
+  The tag or hash of the current commit in `THISDIR` (if `GIT` is
+    defined and `$(THISDIR)/.git` exists).
+
+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