signchanged

Signchanged is a term used in software development to describe a signal or event that is emitted when a property named sign changes value. It is not a standardized language feature, and the exact spelling, casing, and usage vary across frameworks and programming languages. Common variants include signChanged, sign_changed, or a more general propertyNameChanged form depending on naming conventions.

In practice, signchanged (in its various forms) serves as a notification mechanism to observers, data-binding systems, or UI components that rely on reactive updates. Emitting such a signal allows other parts of a program to respond to a change without tight coupling to the property’s setter logic. This aligns with observer patterns, model–view binding, and reactive programming principles.

Typical implementations differ by ecosystem. In signal/slot systems like Qt, a property sign often has an accompanying signal void signChanged(int newSign) that is emitted after the internal value is updated. In languages with property change notifications, such as C# with INotifyPropertyChanged, a change to Sign would trigger a PropertyChanged event with the property name "Sign." JavaScript data-binding and reactive libraries may implement sign change as a watcher or computed dependency invalidation.

Best practices include keeping signal names consistent with framework conventions, emitting signals only after the value has actually changed, and providing the new value (and sometimes the old value) to listeners. See also: signal, event, property change notification, observer pattern, reactive programming.