diff options
Diffstat (limited to 'control')
| -rw-r--r-- | control/monad.scm | 4 | ||||
| -rw-r--r-- | control/monad/procedures.scm | 13 |
2 files changed, 11 insertions, 6 deletions
diff --git a/control/monad.scm b/control/monad.scm index 8bc46bf..f51289d 100644 --- a/control/monad.scm +++ b/control/monad.scm @@ -1,7 +1,7 @@ (define-module (control monad) #:use-module (control monad procedures) #:export (do) - #:re-export (>>=)) + #:re-export (>> >>=)) (define-syntax do (syntax-rules (<- let =) @@ -11,5 +11,5 @@ (>>= val (lambda (var) (do rest ...)))) ((_ a) a) ((_ token rest ...) - (begin token (do rest ...))))) + (>> token (do rest ...))))) diff --git a/control/monad/procedures.scm b/control/monad/procedures.scm index 701f871..2c25d57 100644 --- a/control/monad/procedures.scm +++ b/control/monad/procedures.scm @@ -1,17 +1,22 @@ (define-module (control monad procedures) #:use-module (oop goops) #:use-module (srfi srfi-1) ; concatenate! - #:export (>>=)) + #:export (>> >>=)) (define-generic >>=) -(define-method (>>= (this <null>) - proc) - '()) +(define-method (>>= (this <null>) proc) '()) (define-method (>>= (this <pair>) (proc <procedure>)) (concatenate! (map proc this))) +(define-generic >>) +(define-method (>> (a <null>) (b <null>)) '()) +(define-method (>> (a <pair>) (b <null>)) '()) +(define-method (>> (a <null>) (b <pair>)) '()) +(define-method (>> (a <pair>) (b <pair>)) + (concatenate! (map (constant b) a))) + ;; bind :: Monad m => m a -> (a -> m b) -> m b ;; return :: Monad m => a -> m a ;; map :: Functor f => (a -> b) -> f a -> f b |