Chapter 6 Worked Solutions

Task 1 — Branching choice

Use case when you have discrete statuses:

case InstallmentStatus of
    InstallmentStatus::Open:
        HandleOpen();
    InstallmentStatus::Due:
        HandleDue();
    InstallmentStatus::Paid:
        HandlePaid();
end;

Task 2 — Decision fallback

case InstallmentStatus of
    InstallmentStatus::Open:
        HandleOpen();
    InstallmentStatus::Due:
        HandleDue();
    InstallmentStatus::Paid:
        HandlePaid();
else
    Error('Unsupported installment status: %1', Format(InstallmentStatus));
end;

Task 3 — Loop correction

if LoanRepaymentSchedule.FindSet() then
    repeat
        ProcessInstallment(LoanRepaymentSchedule);
    until LoanRepaymentSchedule.Next() = 0;

Task 4 — Loop intent check

Use for for known counts:

for InstallmentNo := 1 to NumberOfInstallments do
    CreateInstallment(InstallmentNo);

Task 5 — Guard clause

if Amount <= 0 then
    Error('Amount must be greater than zero before posting.');

Task 6 — Reduce nesting depth

Expected answer pattern:

• Extract nested checks to helpers such as ValidateInstallment(Rec); or CanPostInstallment(Rec).
• Keep top-level procedures focused on one control-flow path.
• Return early on invalid data before main processing logic.