Exception Handling

Runtime errors can crash applications if they aren't caught. TypeScript uses modern try...catch...finally blocks to handle runtime errors gracefully.

1. Standard Error Handling Blocks

try {
    let numericalInput = 0;
    if (numericalInput === 0) {
        throw new Error("Cannot complete operations using zero boundaries.");
    }
} catch (runtimeException: unknown) {
    // Intercepts structural errors safely
    if (runtimeException instanceof Error) {
        console.error("Exception handled successfully: " + runtimeException.message);
    }

} finally {
    // Always executes, regardless of whether an error occurred
    console.log("Cleaning up active system connections.");
}

2. Safe Catch Block Type Guarding

In modern TypeScript configurations, caught errors are typed as unknown because JavaScript allows programs to throw any data type at runtime. You should always use instance validation guards before processing details:

try {
    // Perform complex operations...
} catch (unverifiedError: unknown) {
    if (unverifiedError instanceof Error) {
        console.log(`Standard system exception detected: ${unverifiedError.message}`);
    } else {
        console.log("An anomalous, non-standard exception type was thrown.");
    }
}

3. Developing Custom Domain Exceptions

For granular error tracing, extend the base Error class to create custom exception types:

class DatabaseTimeoutException extends Error {
    public timestampRecord: Date;

    constructor(message: string) {
        super(message);
        this.name = "DatabaseTimeoutException";
        this.timestampRecord = new Date();

        // Corrects structural prototype alignment checks for custom classes
        Object.setPrototypeOf(this, DatabaseTimeoutException.prototype);
    }
}