1 files changed, 67 insertions, 0 deletions
diff --git a/lulua/util.py b/lulua/util.py
new file mode 100644
index 0000000..dd35c23
--- /dev/null
+++ b/lulua/util.py
@@ -0,0 +1,67 @@
+# Copyright (c) 2019 lulua contributors
+# 
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+# 
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+# 
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+"""
+Misc utilities
+"""
+
+import os, yaml, pkg_resources
+
+first = lambda x: next (iter (x))
+
+def limit (l, n):
+    it = iter (l)
+    for i in range (n):
+        yield next (it)
+
+class YamlLoader:
+    """
+    Simple YAML loader that searches the current path and the package’s
+    resources (for defaults)
+    """
+
+    __slots__ = ('defaultDir', 'deserialize')
+
+    def __init__ (self, defaultDir, deserialize):
+        self.defaultDir = defaultDir
+        self.deserialize = deserialize
+
+    def __getitem__ (self, k, onlyRes=False):
+        openfunc = []
+        if not onlyRes:
+            openfunc.append (lambda k: open (k, 'r'))
+        # try with and without appending extension
+        openfunc.append (lambda k: pkg_resources.resource_stream (__package__, os.path.join (self.defaultDir, k + '.yaml')))
+        openfunc.append (lambda k: pkg_resources.resource_stream (__package__, os.path.join (self.defaultDir, k)))
+        for f in openfunc:
+            try:
+                with f (k) as fd:
+                    return self.deserialize (yaml.safe_load (fd))
+            except FileNotFoundError:
+                pass
+            except yaml.reader.ReaderError:
+                pass
+
+        raise KeyError
+
+    def __iter__ (self):
+        for res in pkg_resources.resource_listdir (__package__, self.defaultDir):
+            yield self.__getitem__ (res, onlyRes=True)
+