+Interval
+ly_scm2interval (SCM p)
+{
+ return Interval (gh_scm2double (ly_car (p)),
+ gh_scm2double (ly_cdr (p)));
+}
+
+SCM
+ly_interval2scm (Drul_array<Real> i)
+{
+ return gh_cons (gh_double2scm (i[LEFT]),
+ gh_double2scm (i[RIGHT]));
+}
+
+
+
+
+bool
+to_boolean (SCM s)
+{
+ return gh_boolean_p (s) && gh_scm2bool (s);
+}
+
+/*
+ Appendable list L: the cdr contains the list, the car the last cons
+ in the list.
+ */
+SCM
+appendable_list ()
+{
+ SCM s = gh_cons (SCM_EOL, SCM_EOL);
+ gh_set_car_x (s, s);
+
+ return s;
+}
+
+void
+appendable_list_append (SCM l, SCM elt)
+{
+ SCM newcons = gh_cons (elt, SCM_EOL);
+
+ gh_set_cdr_x (ly_car (l), newcons);
+ gh_set_car_x (l, newcons);
+}
+
+
+SCM
+ly_offset2scm (Offset o)
+{
+ return gh_cons (gh_double2scm (o[X_AXIS]), gh_double2scm (o[Y_AXIS]));
+}
+
+Offset
+ly_scm2offset (SCM s)
+{
+ return Offset (gh_scm2double (ly_car (s)),
+ gh_scm2double (ly_cdr (s)));
+}
+
+SCM
+ly_type (SCM exp)
+{
+ char const * cp = "unknown";
+ if (gh_number_p (exp))
+ {
+ cp = "number";
+ }
+ else if (gh_string_p (exp))
+ {
+ cp = "string";
+ }
+ else if (gh_procedure_p (exp))
+ {
+ cp = "procedure";
+ }
+ else if (gh_boolean_p (exp))
+ {
+ cp = "boolean";
+ }
+ else if (gh_pair_p (exp))
+ {
+ cp = "list";
+ }
+
+ return ly_str02scm (cp);
+}
+
+/*
+ convert without too many decimals, and leave a space at the end.
+ */
+
+
+LY_DEFINE(ly_number2string, "ly-number->string", 1, 0,0,
+ (SCM s),
+ " converts @var{num} to a string without generating many decimals. It
+leaves a space at the end.
+")
+{
+ assert (gh_number_p (s));
+
+ char str[400]; // ugh.
+
+ if (scm_exact_p (s) == SCM_BOOL_F)
+ {
+ Real r (gh_scm2double (s));
+
+ if (isinf (r) || isnan (r))
+ {
+ programming_error ("Infinity or NaN encountered while converting Real number; setting to zero.");
+ r = 0.0;
+ }
+
+ sprintf (str, "%8.4f ", r);
+ }
+ else
+ {
+ sprintf (str, "%d ", gh_scm2int (s));
+ }
+
+ return ly_str02scm (str);
+}
+
+/*
+ Undef this to see if GUILE GC is causing too many swaps.
+ */
+
+// #define TEST_GC
+
+#ifdef TEST_GC
+#include <libguile/gc.h>
+
+static void *
+greet_sweep (void *dummy1, void *dummy2, void *dummy3)
+{
+ fprintf (stderr, "entering sweep\n");
+}
+
+static void *
+wave_sweep_goodbye (void *dummy1, void *dummy2, void *dummy3)
+{
+ fprintf (stderr, "leaving sweep\n");
+}
+#endif
+
+
+#include "version.hh"
+LY_DEFINE(ly_version, "ly-version", 0, 0, 0, (),
+ "Return the current lilypond version as a list, e.g.
+@code{(1 3 127 uu1)}.
+")
+{
+ char const* vs = "\' (" MAJOR_VERSION " " MINOR_VERSION " " PATCH_LEVEL " " MY_PATCH_LEVEL ")" ;
+
+ return gh_eval_str ((char*)vs);
+}
+
+LY_DEFINE(ly_unit, "ly-unit", 0, 0, 0, (),
+ "Return the unit used for lengths as a string.")
+{
+ return ly_str02scm (INTERNAL_UNIT);
+}
+
+LY_DEFINE(ly_verbose, "ly-verbose", 0, 0, 0, (),
+ "Return whether lilypond is being run in verbose mode.")
+{
+ return gh_bool2scm (verbose_global_b);
+}
+
+static void
+init_functions ()
+{
+#ifdef TEST_GC
+ scm_c_hook_add (&scm_before_mark_c_hook, greet_sweep, 0, 0);
+ scm_c_hook_add (&scm_before_sweep_c_hook, wave_sweep_goodbye, 0, 0);
+#endif
+}
+
+ADD_SCM_INIT_FUNC (funcs, init_functions);
+
+SCM
+ly_deep_copy (SCM l)
+{
+ if (gh_pair_p (l))
+ {
+ return gh_cons (ly_deep_copy (ly_car (l)), ly_deep_copy (ly_cdr (l)));
+ }
+ else
+ return l;
+}
+
+
+
+
+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\nsym4\nsym5"
+
+ i.e. \n and ' ' can be used interchangeably as separators.
+ */
+SCM
+parse_symbol_list (const char * list)
+{
+ char * s = strdup (list);
+ char *orig = s;
+ SCM create_list = SCM_EOL;
+
+ for (char * p = s; *p; p++)
+ {
+ if (*p == '\n')
+ *p = ' ' ;
+ }
+
+ 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);
+}
+
+String
+print_scm_val (SCM val)
+{
+ String realval = ly_scm2string (ly_write2scm (val));
+ if (realval.length_i () > 200)
+ realval = realval.left_str (100) + "\n :\n :\n" + realval.right_str (100);
+
+ return realval;
+}
+
+bool
+type_check_assignment (SCM sym, SCM val, SCM type_symbol)
+{
+ bool ok = true;
+
+ /*
+ Always succeeds.
+
+
+ TODO: should remove #f from allowed vals?
+ */
+ if (val == SCM_EOL || val == SCM_BOOL_F)
+ return ok;
+
+
+ SCM type_p = SCM_EOL;
+
+ if (gh_symbol_p (sym))
+ type_p = scm_object_property (sym, type_symbol);
+
+ if (type_p != SCM_EOL && !gh_procedure_p (type_p))
+ {
+ warning (_f ("Can't find property type-check for `%s' (%s). Perhaps you made a typing error? Doing assignment anyway.",
+ ly_symbol2string (sym).ch_C (),
+ ly_symbol2string (type_symbol).ch_C ()
+
+ ));
+ }
+ else
+ {
+ if (val != SCM_EOL
+ && gh_procedure_p (type_p)
+ && gh_call1 (type_p, val) == SCM_BOOL_F)
+ {
+ SCM errport = scm_current_error_port ();
+ ok = false;
+ SCM typefunc = scm_primitive_eval (ly_symbol2scm ("type-name"));
+ SCM type_name = gh_call1 (typefunc, type_p);
+
+
+ scm_puts (_f ("Type check for `%s' failed; value `%s' must be of type `%s'",
+ ly_symbol2string (sym).ch_C (),
+ print_scm_val (val),
+ ly_scm2string (type_name).ch_C ()).ch_C (),
+ errport);
+ scm_puts ("\n", errport);
+ }
+ }
+ return ok;
+}
+
+
+/* some SCM abbrevs
+
+ zijn deze nou handig?
+ zijn ze er al in scheme, maar heten ze anders? */
+
+
+/* Remove doubles from (sorted) list */
+SCM
+ly_unique (SCM list)
+{
+ SCM unique = SCM_EOL;
+ for (SCM i = list; gh_pair_p (i); i = ly_cdr (i))
+ {
+ if (!gh_pair_p (ly_cdr (i))
+ || !gh_equal_p (ly_car (i), ly_cadr (i)))
+ unique = gh_cons (ly_car (i), unique);
+ }
+ return scm_reverse_x (unique, SCM_EOL);
+}
+
+/* tail add */
+SCM
+ly_snoc (SCM s, SCM list)
+{
+ return gh_append2 (list, scm_list_n (s, SCM_UNDEFINED));
+}
+
+
+/* Split list at member s, removing s.
+ Return (BEFORE . AFTER) */
+SCM
+ly_split_list (SCM s, SCM list)
+{
+ SCM before = SCM_EOL;
+ SCM after = list;
+ for (; gh_pair_p (after);)
+ {
+ SCM i = ly_car (after);
+ after = ly_cdr (after);
+ if (gh_equal_p (i, s))
+ break;
+ before = gh_cons (i, before);
+ }
+ return gh_cons ( scm_reverse_x (before, SCM_EOL), after);
+
+}