What is the difference between Strategy pattern and Visitor Pattern?

Question

I have trouble understanding these two design patterns.

Can you please give me contextual information or an example so I can get a clear idea and be able to map the dif

Answer 1

If we look at the UML for these two patterns from the GoF book, we see they are nothing alike.

Visitor:

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Strategy:

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Some important differences stand out from the diagrams.

• Strategy is based on composition. Visitor has no composition relationship.
• Strategy is based on coding to an interface. Visitor is based on coding to an implementation.
• Strategy implements one operation in multiple ways. Visitor implements multiple operations.

UML alone does not capture the different motivations driving these patterns.

• Strategy is an object-oriented solution for languages without first-class functions. As modern languages adopt closures or lambdas, there is less need for the Strategy Pattern.
• Visitor is an object-oriented solution for languages without pattern matching or multiple dispatch. As modern languages adopt these features, Visitor too becomes obsolete.