added block expression

boring/parse.py

@@ -91,7 +91,7 @@ class VariableUsage:
 
 @dataclass
 class Expression:
-    expression: Union[LiteralInt, LiteralFloat, FunctionCall, VariableUsage, Operation]
+    expression: Union[LiteralInt, LiteralFloat, FunctionCall, "Block", VariableUsage, Operation]
     type: TypeUsage
 
 
@@ -163,6 +163,7 @@ boring_grammar = r"""
          | variable_usage
          | function_call
          | "(" expression ")"
+         | block
 
     let_statement : "let" identifier "=" expression ";"
                   | "let" identifier ":" type_usage "=" expression ";"

boring/type_checking.py

@@ -139,6 +139,10 @@ class TypeChecker:
             if self.with_function_call(env, type_env, subexpression):
                 changed = True
             return changed
+        if isinstance(subexpression, parse.Block):
+            if self.with_block(env, type_env, subexpression):
+                changed = True
+            return changed
         if isinstance(subexpression, parse.VariableUsage):
             if self.with_variable_usage(env, type_env, subexpression):
                 changed = True