Call By Name vs Call By Sharing

Developers should learn call by name when working with languages that support lazy evaluation or need to delay computation until necessary, such as in Scala for implementing custom control structures or avoiding unnecessary evaluations meets developers should understand call by sharing to avoid common bugs related to mutable objects, such as unintentionally modifying data structures passed to functions, which can lead to side effects and hard-to-debug issues. Here's our take.

Call By Name

Nice Pick

Developers should learn call by name when working with languages that support lazy evaluation or need to delay computation until necessary, such as in Scala for implementing custom control structures or avoiding unnecessary evaluations

Pros

• It is useful in scenarios where arguments might be expensive to compute or have side effects that should only occur if the parameter is actually used, improving performance and enabling more expressive programming patterns like short-circuiting in logical operators
• Related to: scala, lambda-calculus

Cons

• Specific tradeoffs depend on your use case

Call By Sharing

Developers should understand call by sharing to avoid common bugs related to mutable objects, such as unintentionally modifying data structures passed to functions, which can lead to side effects and hard-to-debug issues

Pros

• It is crucial when working with languages that use this mechanism for objects, as it affects how functions interact with arguments like lists, dictionaries, or custom objects, influencing design patterns and memory management
• Related to: parameter-passing, mutable-objects

Cons

• Specific tradeoffs depend on your use case

The Verdict

Use Call By Name if: You want it is useful in scenarios where arguments might be expensive to compute or have side effects that should only occur if the parameter is actually used, improving performance and enabling more expressive programming patterns like short-circuiting in logical operators and can live with specific tradeoffs depend on your use case.

Use Call By Sharing if: You prioritize it is crucial when working with languages that use this mechanism for objects, as it affects how functions interact with arguments like lists, dictionaries, or custom objects, influencing design patterns and memory management over what Call By Name offers.

The Bottom Line

Call By Name wins

Developers should learn call by name when working with languages that support lazy evaluation or need to delay computation until necessary, such as in Scala for implementing custom control structures or avoiding unnecessary evaluations