Overview

Trying to access a key from a Const dict threw a SemanticError stating type mismatch. An ASR pass error was thrown when trying to access values from a Const list, Const tuple and Const str. This was chiefly because the case of a Const value was not addressed in handling subscript indices.

Fix

• Check for Const when visiting subscript indices and handle item access through the contained type in the llvm back-end.

• Throw a SemanticError for immutable types like tuple and str.

• Tuple

• String

• Dictionary

• List

Note

The get attribute of Const dict still throws a SemanticError now. I will push the fix for that in a separate PR.