monads: Add 'lift0'.

* guix/monads.scm (lift0): New variable.
2014-12-02 10:10:51 +01:00 · 2014-12-02 10:10:51 +01:00 · b307c06456
parent 21caa6deeb
commit b307c06456
1 changed files with 2 additions and 1 deletions
--- a/guix/monads.scm
+++ b/guix/monads.scm
@ -41,7 +41,7 @@
            mbegin
            mwhen
            munless
-            lift1 lift2 lift3 lift4 lift5 lift6 lift7 lift
+            lift0 lift1 lift2 lift3 lift4 lift5 lift6 lift7 lift
            listm
            foldm
            mapm
@ -222,6 +222,7 @@ CONDITION is true, return *unspecified* in the current monad."
         (with-monad monad
           (return (proc args ...))))))))

+(define-lift lift0 ())
 (define-lift lift1 (a))
 (define-lift lift2 (a b))
 (define-lift lift3 (a b c))