I have added these things, which are available from scheme/base:
* `hash-has-key?' -- a predicate to test if a key is present in a hash
table.
* `hash-ref!' -- similar to `hash-ref' where the failure argument is
required, and if the key is not found then this failure argument
determines the result but also stores it in the table. (This is the
function version of the `with-hash' macro that I suggested.)
* `in-sequences' -- a new construct for `for' loops, which
concatenates sequences.
* `in-cycle' -- similar to `in-sequences', but the sequences are
repeated in an infinite loop. Note that unlike Sam's version this
does not cache the values -- it looks to me like a dangerous
implicit behavior when you can achieve it explicitly by collecting
the list first explicitly. For example, to cycle a file's contents
you can read it first with `file->bytes'.
--
((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay:
http://www.barzilay.org/ Maze is Life!
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