-minor update to give @early funcs access to pkg data;

-docstring update

src/rez/rezconfig.py

@@ -101,7 +101,8 @@
 # This package will import the code from */src/rezutils/utils.py* (or more
 # specifically, its copy of this sourcefile) and will bind it to the name *utils*.
 #
-# For further information, see [here](Package-Definition-Guide#using-shared-code).
+# For further information, see
+# [here](Package-Definition-Guide#sharing-code-across-package-definition-files).
 #
 package_definition_python_path = None
 
@@ -360,7 +361,8 @@
 # If you define this function, it will be called as the *preprocess function*
 # on every package that does not provide its own, as part of the build process.
 # The given function must be made available by setting the value of
-# *package_definition_build_python_paths* appropriately.
+# [package_definition_build_python_paths](#package_definition_build_python_paths)
+# appropriately.
 #
 # For example, consider the settings:
 #

src/rez/serialise.py

@@ -13,7 +13,7 @@
 from rez.vendor.enum import Enum
 from rez.vendor import yaml
 from contextlib import contextmanager
-from inspect import isfunction
+from inspect import isfunction, getargspec
 from StringIO import StringIO
 import sys
 import os
@@ -170,7 +170,7 @@ def load_py(stream, filepath=None):
     return result
 
 
-def process_python_objects(value, filepath=None):
+def process_python_objects(data, filepath=None):
 
     def _process(value):
         if isinstance(value, dict):
@@ -182,7 +182,17 @@ def _process(value):
             if hasattr(value, "_early"):
                 # run the function now, and replace with return value
                 with add_sys_paths(config.package_definition_build_python_paths):
-                    value_ = value()
+                    func = value
+
+                    spec = getargspec(func)
+                    args = spec.args or []
+                    if len(args) not in (0, 1):
+                        raise ResourceError("@early decorated function must "
+                                            "take zero or one args only")
+                    if args:
+                        value_ = func(data)
+                    else:
+                        value_ = func()
 
                 # process again in case this is a function returning a function
                 return _process(value_)
@@ -204,7 +214,7 @@ def _process(value):
         else:
             return value
 
-    return _process(value)
+    return _process(data)
 
 
 def load_yaml(stream, **kwargs):