Add rulePrecision

Summary: about <distance> rule

Reviewed By: haoxuany

Differential Revision: D28389599

Pulled By: chessai

fbshipit-source-id: 237f6f8ed605ba7d22f40cd338e637ed99565e28

Duckling/Distance/ZH/Corpus.hs

@@ -72,6 +72,7 @@ allExamples = concat
              [ "1.9 m"
              , "1.9米"
              , "米九"
+             , "米九左右"
              ]
   , examples (simple Metre 3.9)
              [ "3.9 m"

Duckling/Distance/ZH/Rules.hs

@@ -220,6 +220,19 @@ ruleIntervalBound2 = Rule
       _ -> Nothing
   }
 
+rulePrecision :: Rule
+rulePrecision = Rule
+  { name = "about <distance>"
+  , pattern =
+    [ dimension Distance
+    , regex "左右"
+    ]
+  , prod = \case
+      (t:_) -> Just t
+      _ -> Nothing
+
+  }
+
 rules :: [Rule]
 rules =
   [ ruleDistCentimeters
@@ -237,4 +250,5 @@ rules =
   , ruleIntervalDash
   , ruleIntervalBound
   , ruleIntervalBound2
+  , rulePrecision
   ]