Primitives for Expressing Iterative Lazy Algorithms
Extends the interpretation of a "promise" to include "lazy" and "eager" promises. Unlike the reference implementation this version does not redefine 'delay'.
For more information see SRFI-45.
Returns a promise, a delayed evaluation of EXPRESSION.
Note that 'delay' is not re-defined here. Mentioned only for completeness.
Returns a promise for EXPRESSION.
The promise will be iteratively forced, overwriting the promise at each step before the next iteration, so as to avoid storage leaks.
Returns a promise but immediately evaluates EXPRESSION.
Not much of a promise, more of a boxed value. For exposition purposes in algorithms.
Assuming the OBJECT is some kind of promise, returns the result of the delayed evaluation.
Assuming the OBJECT is a standard promise, returns the result of the delayed evaluation.
The R5RS 'force'.
Some kind of promise?
The R5RS 'promise?'
Lazy recursive promise?
Eager recursive promise?
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