Cairo Variables and Mutability

Overview

Guide variable bindings in Cairo, including immutability, mutation with mut, constants, and shadowing.

Quick Use

• •Read references/variables-mutability.md before answering.
• •Provide short, compile-ready examples that show correct use of let, let mut, const, and shadowing.
• •When addressing errors, point to the specific rule violated (immutability, type change, or scope).

Response Checklist

• •Decide whether the variable should be immutable, mutable, or constant.
• •If the name is reused or the type changes, prefer shadowing with a new let.
• •For constants, require const, a type annotation, and global scope.

Example Requests

• •"Why does x = 6 fail after let x = 5 in Cairo?"
• •"Should I use mut or shadowing when converting u64 to felt252?"
• •"How do I declare a constant in Cairo?"

Cairo by Example

• •Variable Bindings
• •Mutability
• •Scope and Shadowing
• •Freezing
• •Constants