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Project's home: http://www.hexstreamsoft.com/projects/enhanced-multiple-value-bind/ enhanced-multiple-value-bind provides an enhanced MULTIPLE-VALUE-BIND macro that adds support for lambda keywords by expanding to a MULTIPLE-VALUE-CALL when necessary. This makes catching multiple-value &rest and &key much more lightweight and convenient. A MULTIPLE-VALUE-&BIND alias is supported. Some problems with writing out MULTIPLE-VALUE-CALL with an inline LAMBDA, especially with a big LAMBDA body and trivial form arguments to m-v-c, compared to MULTIPLE-VALUE-BIND, are: - "unnatural" order of evaluation (skip over LAMBDA, evaluate values forms, then "come back" for LAMBDA body); - significant extra indentation for the body. Multiple-value &rest and &key are currently not being used a lot, but the awkwardness of using them up to now might have something to do with this state of affairs. Their usefulness and convenience should now be reassessed. If enhanced-mvb:MULTIPLE-VALUE-BIND is invoked without apparent lambda keywords (symbols beginning with "&"), then it simply expands to cl:MULTIPLE-VALUE-BIND: (enhanced-mvb:multiple-value-bind (a b c) (values 1 2 3) ...) == (multiple-value-bind (a b c) (values 1 2 3) ...) Else, it simply expands to a MULTIPLE-VALUE-CALL with inline LAMBDA: (enhanced-mvb:multiple-value-bind (a b &rest rest) (values 1 2 3) ...) == (multiple-value-call (lambda (a b &rest rest) ...) (values 1 2 3)) An interesting consequence of this is that it's easy to accept an exact number of return values (though I'm not sure why you'd want to): (multiple-value-bind (a b c &optional) (values 1 2 3 4)) error --> "Invalid number of arguments: 4" This follows the same principle as VALUES in FUNCTION type specifiers. CLHS VALUES (type specifier): http://www.lispworks.com/documentation/HyperSpec/Body/t_values.htm To use enhanced-multiple-value-bind, either refer to the provided MULTIPLE-VALUE-BIND directly: ;; A bit long... (enhanced-multiple-value-bind:multiple-value-bind (x y &rest others) (values 1 2 3 4) (values (* x y) others)) => 2, (3 4) ;; Much more managable package nickname. (enhanced-mvb:multiple-value-bind (x y &rest others) (values 1 2 3 4) (values (* x y) others)) => 2, (3 4) Or (:shadowing-import-from #:enhanced-multiple-value-bind #:multiple-value-bind) in your DEFPACKAGE (or with the package nickname, again). Don't (:use)! enhanced-multiple-value-bind also exports MULTIPLE-VALUE-&BIND, with exactly the same functionality, so you can (:import-from #:enhanced-multiple-value-bind #:multiple-value-&bind) in your DEFPACKAGE instead if you want. This library is in the Public Domain. See the UNLICENSE file for details.