feat(value): Allow moving into constituent types

liquid-value/src/values.rs

@@ -77,6 +77,14 @@ impl Value {
         }
     }
 
+    /// Extracts the scalar value if it is a scalar.
+    pub fn into_scalar(self) -> Option<Scalar> {
+        match self {
+            Value::Scalar(s) => Some(s),
+            _ => None,
+        }
+    }
+
     /// Tests whether this value is a scalar
     pub fn is_scalar(&self) -> bool {
         self.as_scalar().is_some()
@@ -98,6 +106,14 @@ impl Value {
         }
     }
 
+    /// Extracts the array value if it is an array.
+    pub fn into_array(self) -> Option<Array> {
+        match self {
+            Value::Array(s) => Some(s),
+            _ => None,
+        }
+    }
+
     /// Tests whether this value is an array
     pub fn is_array(&self) -> bool {
         self.as_array().is_some()
@@ -119,11 +135,27 @@ impl Value {
         }
     }
 
+    /// Extracts the object value if it is a object.
+    pub fn into_object(self) -> Option<Object> {
+        match self {
+            Value::Object(s) => Some(s),
+            _ => None,
+        }
+    }
+
     /// Tests whether this value is an object
     pub fn is_object(&self) -> bool {
         self.as_object().is_some()
     }
 
+    /// Extracts the nil value if it is nil
+    pub fn as_nil(&self) -> Option<()> {
+        match *self {
+            Value::Nil => Some(()),
+            _ => None,
+        }
+    }
+
     /// Tests whether this value is nil
     pub fn is_nil(&self) -> bool {
         match *self {