SICP covers this too: http://mitpress.mit.edu/sicp/full-text/book/book-Z-H-28.html#%_sec_4.3 http://mitpress.mit.edu/sicp/full-text/book/book-Z-H-28.html... Th

SICP covers this too: http://mitpress.mit.edu/sicp/full-text/book/book-Z-H-28.html#%_sec_4.3 http://mitpress.mit.edu/sicp/full-text/book/book-Z-H-28.html... The references are better than the posted link. I have found a couple of uses for this in the past and deparately tried to port the examples to C# (unsuccessfully).