;;;; This file is part of LilyPond, the GNU music typesetter.
;;;;
-;;;; Copyright (C) 2005--2012 Erik Sandberg <mandolaerik@gmail.com>
+;;;; Copyright (C) 2005--2014 Erik Sandberg <mandolaerik@gmail.com>
;;;;
;;;; LilyPond is free software: you can redistribute it and/or modify
;;;; it under the terms of the GNU General Public License as published by
(acons elt lineage alist))
classlist class))))
+(define all-event-classes
+ (fold (lambda (elt classlist)
+ (event-class-cons (cdr elt) (car elt) classlist))
+ '() event-classes))
+
+;; Maps event-class to a list of ancestors (inclusive)
+(define ancestor-lookup (make-hash-table (length all-event-classes)))
+
+(define (ancestor-lookup-initialize)
+ (hash-clear! ancestor-lookup)
+ (for-each (lambda (ent) (hashq-set! ancestor-lookup (car ent) ent))
+ all-event-classes))
+
+(ancestor-lookup-initialize)
+(call-after-session ancestor-lookup-initialize)
+
;; Each class will be defined as
;; (class parent grandparent .. )
;; so that (eq? (cdr class) parent) holds.
+(define-public (define-event-class class parent)
+ "Defines a new event @code{class} derived from @code{parent}, a
+previously defined event class."
+ (let ((parentclass (ly:make-event-class parent)))
+ (cond
+ ((ly:make-event-class class)
+ (ly:error (_ "Cannot redefine event class `~S'") class))
+ ((not parentclass)
+ (ly:error (_ "Undefined parent event class `~S'" parentclass)))
+ (else
+ (hashq-set! ancestor-lookup
+ class
+ (cons class parentclass))))
+ *unspecified*))
+
+;; TODO: Allow entering more complex classes, by taking unions.
+(define-public (ly:make-event-class leaf)
+ (hashq-ref ancestor-lookup leaf))
+
(define-public (ly:in-event-class? ev cl)
"Does event @var{ev} belong to event class @var{cl}?"
(memq cl (ly:event-property ev 'class)))
-(define-public all-event-classes
- (fold (lambda (elt classlist)
- (event-class-cons (cdr elt) (car elt) classlist))
- '() event-classes))
-
;; does this exist in guile already?
(define (map-tree f t)
(cond