J operator

In computer science, Peter Landin's J operator is a programming construct that post-composes a lambda expression with the continuation to the current lambda-context. The resulting “function” is first-class and can be passed on to subsequent functions, where if applied it will return its result to the continuation of the function in which it was created.

One can define the return statement as a first-class object by taking the J of the identity function. It can then be passed on to other functions and applied there to return from the function in which the “return” was created.

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