Allow matchers to be used in case equality

src/spectator/matchers/matcher.cr

@@ -1,3 +1,4 @@
+require "../value"
 require "./match_data"
 
 module Spectator::Matchers
@@ -22,6 +23,19 @@ module Spectator::Matchers
     # A successful match with `#match` should normally fail for this method, and vice-versa.
     abstract def negated_match(actual : Expression(T)) : MatchData forall T
 
+    # Compares a matcher against a value.
+    # Enables composable matchers.
+    def ===(actual : Expression(T)) : Bool
+      match(actual).matched?
+    end
+
+    # Compares a matcher against a value.
+    # Enables composable matchers.
+    def ===(other) : Bool
+      expression = Value.new(other)
+      match(expression).matched?
+    end
+
     private def match_data_description(actual : Expression(T)) : String forall T
       match_data_description(actual.label)
     end