Separate cue lists from playbacks and crossfades

1 files changed, 17 insertions, 1 deletions

diff --git a/guile/starlet/utils.scm b/guile/starlet/utils.scm
index 16e3364..2046a0a 100644
--- a/guile/starlet/utils.scm
+++ b/guile/starlet/utils.scm
@@ -20,13 +20,15 @@
 ;;
 (define-module (starlet utils)
   #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-8)
   #:export (print-hash-table
             copy-hash-table
             in-range
             mean
             flatten-sublists
             more-than-one
-            hirestime))
+            hirestime
+            categorize))
 
 
 (define (print-hash-table ht)
@@ -83,3 +85,17 @@
        (/ (cdr a)
           1000000))))
 
+
+(define (categorize-rec predicates items so-far)
+  (if (nil? predicates)
+    (reverse (cons items so-far))
+    (receive
+      (selected-items remaining-items)
+      (partition (car predicates) items)
+      (categorize-rec (cdr predicates)
+                      remaining-items
+                      (cons selected-items so-far)))))
+
+
+(define (categorize items . predicates)
+  (apply values (categorize-rec predicates items '())))