Error Handling

Error Handling in Batch

Learn how Windows Batch scripts detect and respond to failures using ERRORLEVEL, exit codes, and a centralized GOTO :error pattern.

MFC Exception Handling

How MFC's CException hierarchy works, how to catch and clean up MFC exceptions correctly, and how they interact with standard C++ exceptions.

Faults and Exception Handling

Learn how WCF translates .NET exceptions into SOAP faults, how to design typed FaultContracts, and how to centralize fault handling with IErrorHandler.

Error Handling with IfError

IfError lets a Power Fx formula catch a runtime error and substitute a fallback value instead of letting the error propagate and break the app's UI.

Testing Exceptions with toThrow

Learn how to assert that a function throws an error using toThrow, including matching messages, error types, and async rejections.

Retries and Error Handling

Configuring per-task retries, retry delays, callbacks, and trigger rules so Airflow DAGs recover gracefully from transient failures.

Error Handling with Try/Catch

Understand PowerShell's terminating vs non-terminating errors and how try/catch/finally, -ErrorAction, and $ErrorActionPreference work together to handle failu…

Error Handling and Retries

How to build try/catch-style error handling with Configure run after, retry policies, Scopes, and Terminate.

Error Handling with TRY/CATCH

Learn how TRY...CATCH blocks intercept T-SQL runtime errors, how to inspect them with the ERROR_ functions, and how to combine them safely with transactions.

Error Handling in Fortran

Learn Fortran's status-code-based approach to error handling, covering I/O error checking, allocation failures, and structured patterns for building robust pro…

Exception Handling in Pascal

Learn how try..except and try..finally let Object Pascal programs handle errors gracefully and guarantee cleanup.

Exception Handling in Apex

Learn how to use try/catch/finally, built-in and custom exception types, and partial-success DML patterns to write resilient Apex code.

Error Handling in Socket.IO

Learn the distinct categories of Socket.IO errors — connection errors, disconnect reasons, and acknowledgement failures — and how to handle each robustly.

Error Handling with require, revert, assert

Solidity handles errors by reverting state changes. Learn when to use require for input validation, revert with custom errors for gas-efficient failures, and a…

Error Handling with On Error

Intercept run-time errors gracefully in VBA using On Error statements, the Err object, and disciplined cleanup patterns.

Error Handling with Try/Catch

Learn structured exception handling in VB.NET using Try, Catch, Finally, and Throw to write robust code that gracefully handles runtime errors.

Error Handling with catch and try

How Tcl scripts detect, inspect, and recover from runtime errors using the catch command and the more structured try/on/finally syntax.

Error Handling and Conditions

How Common Lisp's condition system goes beyond try/catch, letting programs signal, inspect, and interactively recover from errors using restarts.

Error Handling with NSError

The conventions and patterns Objective-C uses for reporting recoverable errors via NSError, as distinct from exceptions for programmer errors.

Error Handling in D

Learn D's split between recoverable Exceptions and unrecoverable Errors, the scope(exit)/failure/success guards, and std.exception helpers like enforce and not…

Exception Handling in Dart

Learn how Dart represents and handles runtime errors using try/catch/finally, custom exception types, and the distinction between Exceptions and Errors.

Error Handling in Lua (pcall/error)

Learn how Lua signals and catches errors using error(), pcall(), and xpcall(), instead of try/catch exceptions.

Error Handling in Groovy

How Groovy handles exceptions, including its unchecked-exceptions model, try/catch/finally, multi-catch, custom exceptions, and null-safe operators that reduce…

Error Handling in Erlang

Erlang handles failure through a distinctive combination of try/catch exception handling and the 'let it crash' philosophy, where supervisors, not defensive co…

Go Cheat Sheet

Go syntax, goroutines, channels, error handling, and package structure for writing concurrent, statically typed programs.

Rust Cheat Sheet

Rust ownership, borrowing, pattern matching, error handling with Result, and core syntax for memory-safe systems code.

Zig Cheat Sheet

Core Zig syntax covering variables, error unions, control flow, structs, and compile-time features for systems programming.

Ada Cheat Sheet

Key Ada syntax covering strong typing, control flow, packages, and exception handling for safety-critical software.

Python Exception Handling Cheat Sheet

Python error handling covering try/except/else/finally, catching multiple exceptions, raising and chaining errors, and custom exceptions.

Python AsyncIO Cheat Sheet

Covers async/await syntax, creating and gathering concurrent tasks, synchronization primitives, and timeout/error handling patterns.

JavaScript Async/Await Cheat Sheet

Covers async function syntax, error handling with try/catch, and running promises sequentially versus concurrently with Promise combinators.

JavaScript Error Handling Cheat Sheet

Covers try/catch/finally, custom Error subclasses, handling errors in promises and async/await, and the ES2022 error cause chain.

Java Exception Handling Cheat Sheet

Covers try/catch/finally blocks, try-with-resources, custom checked exceptions, checked versus unchecked exception types, and exception cause chaining in Java.

C# Async/Await Cheat Sheet

Explains async/await in C#, Task combinators like WhenAll and WhenAny, cancellation tokens, exception handling, and common concurrency pitfalls to avoid.

Go Error Handling Cheat Sheet

Covers Go's explicit error return values, wrapping errors with %w, errors.Is and errors.As, custom error types, and panic/recover semantics.

Rust Error Handling Cheat Sheet

Covers the Result and Option types, the ? operator, custom error types, and idiomatic patterns for propagating and handling errors in Rust.

Shell Scripting Deep Dive Cheat Sheet

Advanced Bash scripting patterns including parameter expansion, error handling, arrays, and safe scripting practices.

Canary Deployment Cheat Sheet

Techniques for gradually shifting production traffic to a new version while monitoring metrics to catch regressions early.

Elm Cheat Sheet

Core syntax, the Elm Architecture (Model/Update/View), types, and JSON decoding for building reliable, no-runtime-exceptions front-end apps.

AWS Step Functions Cheat Sheet

ASL state types, error handling, and CLI/SDK commands for building and running serverless workflow orchestrations.

HTTP Status Codes Explained in Detail

HTTP status codes are three-digit responses that classify the outcome of a request into five families — 1xx informational, 2xx success, 3xx redirection, 4xx cl…

What is a Dead Letter Queue?

A dead letter queue (DLQ) is a separate holding queue where messages are routed after they repeatedly fail to be processed successfully, so a poison message ca…

What is an HTTP Status Code?

An HTTP status code is a three-digit number returned by a server in every HTTP response, grouped by its first digit into a class (1xx informational, 2xx succes…

Promises vs async/await: What Is the Difference?

Promises and async/await are the same underlying mechanism for handling asynchronous results — async/await is syntactic sugar built on top of Promises that let…

What Is Optional Chaining in JavaScript?

Optional chaining, written with the `?.` operator, lets you safely access a nested property, call a method, or index into an array without throwing a TypeError…

What Is Strict Mode in JavaScript?

Strict mode is an opt-in restricted variant of JavaScript, enabled with the literal string “use strict”, that turns silent mistakes into thrown errors, disable…

What Are Error Boundaries in React?

An error boundary is a React component that catches JavaScript errors thrown anywhere in its child component tree during rendering, in lifecycle methods, or in…

What Do the HTTP Status Code Families Mean?

HTTP status codes are grouped into five families by their leading digit — 1xx informational, 2xx success, 3xx redirection, 4xx client error, and 5xx server err…

Promise.all vs Promise.allSettled: When to Use Each?

Promise.all resolves with an array of values only if every input promise fulfills, and it rejects immediately with the first rejection reason if any one fails,…

Promise.race vs Promise.any: What Sets Them Apart?

Promise.race settles as soon as any one input promise settles — whether it fulfills or rejects — mirroring whatever that first promise did, while Promise.any s…

What Are State Machines and Why Use Them in Frontend Code?

A state machine models a UI as a finite set of named states plus explicit, allowed transitions between them, so instead of scattering booleans like isLoading,…

What Are Optimistic UI Updates and How Do You Implement Them?

Optimistic UI updates mean the interface applies the expected result of an action immediately, before the server confirms it, and only rolls back to the previo…