Scalar::Lazy

Scalar::Lazy is a Perl module that provides lazy evaluation functionality. It offers an easy and efficient way to delay evaluation until the value is actually needed. The module's features are demonstrated in the SYNOPSIS section of the documentation, which presents examples of how to use Scalar::Lazy.

The first example shows how to create a lazy scalar using the lazy() function provided by the module. Instead of immediately evaluating the value, the code only creates a closure around it. The value will be evaluated only when it is actually needed, which can save a lot of processing time in certain cases.

The second example demonstrates how to implement the Y-combinator in Perl using Scalar::Lazy. The code creates a higher-order function that takes another function as an argument and returns a closure that performs lazy evaluation of its result. This example illustrates the power and flexibility of Scalar::Lazy.

In the DISCUSSION section of the documentation, the module's implementation details are explained. The traditional way of implementing lazy evaluation is to use closures to wrap the value, but Scalar::Lazy provides a simpler and more efficient alternative. By marking a variable as lazy using prototypes, the module automatically handles the evaluation of the value when it is needed.

Overall, Scalar::Lazy is a useful module for anyone who wants to take advantage of lazy evaluation in Perl. Its simple and efficient implementation makes it an excellent choice for developers who need to optimize their code for performance.