Add simple stateful stack implementation.

1 files changed, 12 insertions, 3 deletions

diff --git a/control/monad/state.scm b/control/monad/state.scm
index e369d5d..1097567 100644
--- a/control/monad/state.scm
+++ b/control/monad/state.scm
@@ -2,9 +2,12 @@
   #:use-module (oop goops)
   #:use-module (ice-9 match)
   #:use-module (control monad)
-  #:export (make-state return-state
-                       get put
-                       run-state)
+  #:export (return-state run-state
+                         get put
+                         ;; TODO
+                         ;; should these even be exported?
+                         define-stateful
+                         define-stateful-method)
   #:re-export (>>= >>))
 
 
@@ -28,6 +31,12 @@
   "Creates a state object from a State procedure"
   (make <state> #:proc proc))
 
+;;; Define a procedure which is in the state monad. This means that it takes a
+;;; state list as a curried argument, and it's return is wrappen in a <state>
+;;; object.
+;;; It's fully possible to create stateful objects without these macros, but it's
+;;; ill adviced since that would just be boilerplate.
+
 (define-syntax-rule (define-stateful ((proc args ...) st) body ...)
   (define (proc args ...)
     (make-state