+
+
+SCM
+ly_assoc_chain (SCM key, SCM achain)
+{
+ if (gh_pair_p (achain))
+ {
+ SCM handle = scm_assoc (key, ly_car (achain));
+ if (gh_pair_p (handle))
+ return handle;
+ else
+ return ly_assoc_chain (key, ly_cdr (achain));
+ }
+ else
+ return SCM_BOOL_F;
+}
+
+/* looks the key up in the cdrs of the alist-keys
+ - ignoring the car and ignoring non-pair keys.
+ Returns first match found, i.e.
+
+ alist = ((1 . 10)
+ ((1 . 2) . 11)
+ ((2 . 1) . 12)
+ ((3 . 0) . 13)
+ ((4 . 1) . 14) )
+
+I would like (ly_assoc_cdr 1) to return 12 - because it's the first
+element with the cdr of the key = 1. In other words (alloc_cdr key)
+corresponds to call
+
+(alloc (anything . key))
+
+
+
+*/
+SCM
+ly_assoc_cdr (SCM key, SCM alist)
+{
+ if (gh_pair_p (alist)) {
+ SCM trykey = ly_caar(alist);
+ if(gh_pair_p(trykey) && to_boolean(scm_equal_p(key,ly_cdr(trykey))))
+ return ly_car(alist);
+ else
+ return ly_assoc_cdr (key, ly_cdr (alist));
+ }
+ else
+ return SCM_BOOL_F;
+}
+
+/*
+ LIST has the form "sym1 sym2 sym3"
+ */
+SCM
+parse_symbol_list (const char * list)
+{
+ char * s = strdup (list);
+ char *orig = s;
+ SCM create_list = SCM_EOL;
+ if (!s[0] )
+ s = 0;
+
+ while (s)
+ {
+ char *next = strchr (s, ' ');
+ if (next)
+ *next++ = 0;
+
+ create_list = gh_cons (ly_symbol2scm (s), create_list);
+ s = next;
+ }
+
+ free (orig);
+ return create_list;
+}
+
+
+SCM
+ly_truncate_list (int k, SCM l )
+{
+ if (k == 0)
+ {
+ l = SCM_EOL;
+ }
+ else
+ {
+ SCM s = l;
+ k--;
+ for (; gh_pair_p (s) && k--; s = ly_cdr (s))
+ ;
+
+ if (gh_pair_p (s))
+ {
+ gh_set_cdr_x (s, SCM_EOL);
+ }
+ }
+ return l;
+}
+
+SCM my_gh_symbol2scm (const char* x)
+{
+ return gh_symbol2scm ((char*)x);
+}