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What is the difference between Go's lazy and eager evaluation of expressions?

In Go, expressions can be evaluated using either lazy or eager evaluation.

Eager evaluation, also known as strict evaluation, evaluates all expressions in a statement before executing the statement. This means that all expressions are evaluated regardless of whether or not their values are needed. For example, in the expression a + b + c, all three variables a, b, and c will be evaluated before the addition operation is performed. This can be inefficient if some of the expressions have expensive calculations or if they are not necessary for the final result.

Lazy evaluation, on the other hand, evaluates expressions only when their values are needed. This means that some expressions may never be evaluated if they are not necessary for the final result. Go does not have built-in support for lazy evaluation, but it is possible to simulate lazy evaluation using functions and closures. For example, instead of calculating a value upfront, a function can be used to calculate the value on demand when it is needed.

Lazy evaluation can be more efficient than eager evaluation in certain situations, especially when dealing with large data sets or complex computations. However, it can also make code harder to understand and debug, as the order of evaluation may not be obvious.

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