using string return values to signal errors #patterns #js

100%

using string return values to signal errors #patterns #js

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Last edited Oct 2, 2018

Created on Oct 2, 2018

This example demonstrates a JavaScript pattern for signaling errors by returning string messages instead of throwing exceptions. The code defines a `handleAddOption` function that returns a descriptive error string when validation fails, such as an empty input or a duplicate option, and otherwise updates state via the React `setState` method. A separate caller checks whether the return value is a string to conditionally trigger error handling. The snippet relies on React’s state management and plain JavaScript control flow, with no external libraries or data sources involved.

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