Document input/output object shape

Author: goto-bus-stop

readme.markdown

@@ -149,15 +149,30 @@ in `process.env.NODE_PATH`
 Input objects should be string filenames or objects with these parameters:
 
 * `row.file` - filename
+* `row.entry` - whether to treat this file as an entry point, defaults to
+  `true`. Set to `false` to include this file, but not run it automatically.
 * `row.expose` - name to be exposed as
-* `row.noparse` when true, don't parse the file contents for dependencies
+* `row.noparse` - when true, don't parse the file contents for dependencies
 
 or objects can specify transforms:
 
 * `row.transform` - string name, path, or function
 * `row.options` - transform options as an object
 * `row.global` - boolean, whether the transform is global
 
+# output objects
+
+Output objects describe files with dependencies. They have these properties:
+
+* `row.id` - an identifier for the file, used in the `row.deps` prperty
+* `row.file` - path to the source file
+* `row.entry` - true if the file is an entry point
+* `row.expose` - name to be exposed as
+* `row.source` - source file content as a string
+* `row.deps` - object describing dependencies. The keys are strings as used
+  in `require()` calls in the file, and values are the row IDs (file paths)
+  of dependencies.
+
 # events
 
 ## d.on('transform', function (tr, file) {})