Introduce new type for attribute names

There's a serious problem with the design so far, where symbols are used
for attribute names (intensity, strobe, colour etc), and also for
attribute values (on, off, random etc).  There's no way for 'at' to
tell the difference between the two.  For example, this form is
ambiguous:  (at myfixture 'strobe 'on)

This commit introduces a new class, <starlet-attribute>, to replace the
use of symbols here.  The attributes are enumerated in (starlet attributes),
and new ones can be added later.  The attribute objects remember their
'canonical' names, to allow states to be printed.

Apart from solving the ambiguity problem, this has two further
advantages.  First, attribute names no longer need to be quoted
everywhere.  Second, multiple names can be used to refer to the same
attribute.  For example: (define color colour).

1 files changed, 31 insertions, 30 deletions

diff --git a/guile/starlet/fixture-library/robe/mmxwashbeam.scm b/guile/starlet/fixture-library/robe/mmxwashbeam.scm
index 282bd0f..a41c80d 100644
--- a/guile/starlet/fixture-library/robe/mmxwashbeam.scm
+++ b/guile/starlet/fixture-library/robe/mmxwashbeam.scm
@@ -21,6 +21,7 @@
 (define-module (starlet fixture-library robe mmxwashbeam)
   #:use-module (starlet scanout)
   #:use-module (starlet fixture)
+  #:use-module (starlet attributes)
   #:use-module (starlet utils)
   #:use-module (starlet colours)
   #:export (<robe-mmxwashbeam-mode1>))
@@ -31,37 +32,37 @@
   <robe-mmxwashbeam-mode1>
 
   (fixture-attributes
-    (attr-continuous 'intensity '(0 100) 0)
-    (attr-continuous 'pan '(0 540) 270)
-    (attr-continuous 'tilt '(0 270) 135)
-    (attr-list 'strobe '(#t #f) #f)
-    (attr-list 'colwheel '(#f red blue orange green amber uv) #f)
-    (attr-list 'gobo '(#f iris gobo1 gobo2 gobo3 gobo4 gobo5 gobo6) #f)
-    (attr-list 'beamtype '(beam beamwash beamwashext) 'beam)
-    (attr-colour 'colour white)
-    (attr-continuous 'zoom '(0 100) 0)
-    (attr-continuous 'focus '(0 100) 0)
-    (attr-continuous 'barndoor-rot '(0 180) 90)
-    (attr-continuous 'barndoor1 '(0 180) 0)
-    (attr-continuous 'barndoor2 '(0 100) 0)
-    (attr-continuous 'barndoor3 '(0 100) 0)
-    (attr-continuous 'barndoor4 '(0 100) 0))
+    (attr-continuous intensity '(0 100) 0)
+    (attr-continuous pan '(0 540) 270)
+    (attr-continuous tilt '(0 270) 135)
+    (attr-list strobe '(#t #f) #f)
+    (attr-list colwheel '(#f red blue orange green amber uv) #f)
+    (attr-list gobo '(#f iris gobo1 gobo2 gobo3 gobo4 gobo5 gobo6) #f)
+    (attr-list beamtype '(beam beamwash beamwashext) 'beam)
+    (attr-colour colour white)
+    (attr-continuous zoom '(0 100) 0)
+    (attr-continuous focus '(0 100) 0)
+    (attr-continuous barndoor-rot '(0 180) 90)
+    (attr-continuous barndoor1 '(0 180) 0)
+    (attr-continuous barndoor2 '(0 100) 0)
+    (attr-continuous barndoor3 '(0 100) 0)
+    (attr-continuous barndoor4 '(0 100) 0))
 
-  (set-chan16 33 (percent->dmxval16 (get-attr 'intensity)))
+  (set-chan16 33 (percent->dmxval16 (get-attr intensity)))
 
-  (set-chan16 1 (scale-to-range (get-attr 'pan) '(0 540) '(0 65535)))
-  (set-chan16 3 (scale-to-range (get-attr 'tilt) '(0 270) '(0 65535)))
+  (set-chan16 1 (scale-to-range (get-attr pan) '(0 540) '(0 65535)))
+  (set-chan16 3 (scale-to-range (get-attr tilt) '(0 270) '(0 65535)))
 
-  (set-chan8 32 (if (get-attr 'strobe) 70 255))
+  (set-chan8 32 (if (get-attr strobe) 70 255))
 
-  (set-chan16 19 (percent->dmxval16 (get-attr 'zoom)))
-  (set-chan16 21 (percent->dmxval16 (get-attr 'focus)))
+  (set-chan16 19 (percent->dmxval16 (get-attr zoom)))
+  (set-chan16 21 (percent->dmxval16 (get-attr focus)))
 
-  ;;(set-chan 24 (number->dmxval (get-attr 'barndoor-rot) '(0 180)))
-  (set-chan8 25 (percent->dmxval8 (get-attr 'barndoor1)))
-  (set-chan8 26 (percent->dmxval8 (get-attr 'barndoor2)))
-  (set-chan8 27 (percent->dmxval8 (get-attr 'barndoor3)))
-  (set-chan8 28 (percent->dmxval8 (get-attr 'barndoor4)))
+  ;;(set-chan 24 (number->dmxval (get-attr barndoor-rot) '(0 180)))
+  (set-chan8 25 (percent->dmxval8 (get-attr barndoor1)))
+  (set-chan8 26 (percent->dmxval8 (get-attr barndoor2)))
+  (set-chan8 27 (percent->dmxval8 (get-attr barndoor3)))
+  (set-chan8 28 (percent->dmxval8 (get-attr barndoor4)))
 
   (set-chan8 7 (assv-ref '((#f . 0)
                            (red . 18)
@@ -70,7 +71,7 @@
                            (green . 73)
                            (amber . 91)
                            (uv . 110))
-                         (get-attr 'colwheel)))
+                         (get-attr colwheel)))
 
   (set-chan8 15 (assv-ref '((#f . 0)
                             (iris . 5)
@@ -80,14 +81,14 @@
                             (gobo4 . 22)
                             (gobo5 . 26)
                             (gobo6 . 30))
-                          (get-attr 'gobo)))
+                          (get-attr gobo)))
 
   (set-chan8 18 (assv-ref '((beam . 0)
                             (beamwash . 35)
                             (beamwashext . 45))
-                          (get-attr 'beamtype)))
+                          (get-attr beamtype)))
 
-  (let ((cmy (colour-as-cmy (get-attr 'colour))))
+  (let ((cmy (colour-as-cmy (get-attr colour))))
     (set-chan8 9 (percent->dmxval8 (car cmy)))
     (set-chan8 10 (percent->dmxval8 (cadr cmy)))
     (set-chan8 11 (percent->dmxval8 (caddr cmy)))))