add match

Author: czheo

syntax_sugar/__init__.py

@@ -4,4 +4,5 @@
 from .infix import *
 from .stream import *
 from .placeholder import *
+from .match import *
 from eventlet import green

syntax_sugar/match.py

@@ -0,0 +1,31 @@
+from .pipe import END
+
+__all__ = [
+    'match',
+]
+
+class match:
+    def __init__(self, x):
+        self.x = x
+        self.done = False
+        self.result = None
+
+    def __or__(self, rhs):
+        if rhs is END:
+            return self.result
+        if self.done:
+            return self
+        if isinstance(rhs, dict):
+            result = rhs.get(self.x, None)
+            if result:
+                self.done = True
+                self.result = result
+            return self
+        if isinstance(rhs, tuple):
+            patt, fn = rhs
+            if self.x == patt:
+                self.done = True
+                self.result = fn()
+            return self
+        else:
+            raise SyntaxError('Bad match syntax.')