Spec #38.4: Implement 1D array assignment (write)

[treytomes]

Description

Assign values to array elements using LET statement with array subscripts. Extends LET statement to support: LET A(i) = value

ECMA-55 References

• ECMA55-ARR-007: Array assignment syntax
• ECMA55-VAR-012: Subscript bounds checking on write

Acceptance Criteria

• Parse LET A(i) = expression
• Assignment stores value at subscript
• Bounds checking on write operations
• Out-of-bounds assignment throws error
• Multiple assignments work correctly
• Works with complex expressions
• All tests pass
• Test coverage ≥ 80%

Parent Issue

Part of #38 - Implement DIM and OPTION BASE for array support

Estimated Effort

2-3 hours

Dependencies

Depends on Spec #38.3 (array read access)