Fix Monad issue in Haskell generator

tested/languages/haskell/generators.py

@@ -252,7 +252,7 @@ def convert_execution_unit(pu: PreparedExecutionUnit) -> str:
  )
  else:
  assert isinstance(tc.input, PreparedTestcaseStatement)
- # In Haskell we do not actually have statements, so we need to keep them separate.
+ # In Haskell we do not have statements, so we need to keep them separate.
  # Additionally, exceptions with "statements" are not supported at this time.
  if is_statement_strict(tc.input.statement):
  result += (
@@ -262,30 +262,30 @@ def convert_execution_unit(pu: PreparedExecutionUnit) -> str:
  )
  else:
  result += indent + f"result{i1} <- catch\n"
- result += (
- indent * 2
- + f"({convert_statement(tc.input.unwrapped_input_statement(), True)}\n"
- )
+ result += indent * 2 + f"(do\n" # Start a `do` block
  id_result = tc.input.input_statement("r")
+ result += (
+ indent * 3
+ + f"r <- {convert_statement(tc.input.unwrapped_input_statement(), True)}\n"
+ ) # Bind the result to 'r'
  if isinstance(id_result, Identifier):
- # In this case, we don't catch the value in the sendValues function.
- # This results in pure value instead of an IO monad, so lift the value into the monad.
  result += (
- indent * 3
- + f">>= \\r -> return {convert_statement(id_result)}\n"
- )
+ indent * 3 + f"sendValue {convert_statement(id_result)}\n"
+ ) # Send the value if it's an identifier
  else:
  result += (
- indent * 3 + f">>= \\r -> {convert_statement(id_result)}\n"
- )
+ indent * 3 + convert_statement(id_result) + "\n"
+ ) # Otherwise, execute the statement
+ result += indent * 3 + "return ()\n" # Explicitly return unit
+ result += indent * 2 + ") (\\e -> do\n" # Handle exceptions
  result += (
  indent * 3
- + f">> let ee = (Nothing :: Maybe SomeException) in {convert_statement(tc.exception_statement('ee'))})\n"
+ + f"let ee = (Just (e :: SomeException)) in {convert_statement(tc.exception_statement('ee'))}\n"
  )
  result += (
- indent * 2
-  + f"(\\e -> let ee = (Just (e :: SomeException)) in {convert_statement(tc.exception_statement('ee'))})\n"
- )
+ indent * 3 + "return ()\n"
+ ) # Explicitly return unit in the exception case
+ result += indent * 2 + ")\n" # End the `catch` block
  result += indent + ctx.after + "\n"
  result += indent + 'putStr ""\n'