The Maybe and Either Monads
Explore the use of Maybe and Either monads in PHP for robust error handling. Understand how these sum types encapsulate success and error values, enabling cleaner, composable code without exceptions. Learn to apply bind and map methods to manage computations safely and improve program logic.
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Sum types are especially useful for adding flow control to error handling. In Maybe and Either sum types, we have two monads that are presentable as type-classes in PHP. They’re versatile functors that can carry values in their objects to which computations/functions can be bound through functor methods. Their suitability for cleaner error handling is such that they encapsulate two subtypes for success and error values that are transformable using the bind and map method operations.
The Maybe monad
The Maybe monad is a sum type that stands out because a value defined or used within its context is either Just or Nothing (Some or Nothing in other domains). This duality means that, depending on the situation, a Maybe can only be Just or Nothing, much like a boolean.
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The value subsumed in a
Just...