Defensive programming
Defensive programming is a technique that anticipates invalid inputs, failures, misuse, and unsafe states and explicitly guards against their harmful effects.
Object-Oriented Software Design in C++
A programming technique that validates inputs and guards against invalid states or programming errors.
- How it is used
- Guards object construction and search operations against programming errors in a book-catalogue design.
- How deep it goes
- Explains runtime parameter checks through a variant-backed map and constructor assertions, while deferring broader checking in short examples.
- Examples
- Uses typed book attributes, constructor assertions, catalogue searches, and partial queries such as genre and author.
- What you can do after
- Apply runtime validation to construct only proper objects from parameter values.
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Software Design for Python Programmers
Defensive programming is a technique that validates inputs and guards against programming errors to preserve valid program states.
- How it is used
- Uses runtime checks to prevent invalid objects and guard application state against programming errors.
- How deep it goes
- Shows constructor assertions and matching behavior, while noting that broader examples generally omit parameter checks.
- Examples
- Uses typed book attributes, invalid-value prevention, case-insensitive author matching, and partial catalogue searches.
- What you can do after
- Build valid Python domain objects and diagnose invalid parameter values before they enter the application.
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Related concepts
- try-catch statementuses · A try-catch statement is a control-flow construct that executes code under exception handling and transfers control to a matching handler when an exception is raised.
- validationhas part · The process of checking data, behavior, systems, models, or results against defined criteria to assess their correctness, suitability, or acceptability.
- NullPointerExceptionaddresses · NullPointerException is a Java runtime exception raised when code improperly dereferences or otherwise uses a null reference where an object is required.
- illegal stateaddresses · An illegal state is a program or system state that violates constraints required by its data model, domain rules, or specification.
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