1 files changed, 149 insertions, 0 deletions
diff --git a/range.c b/range.c
new file mode 100644
index 0000000000..816ce27a1a
--- /dev/null
+++ b/range.c
@@ -0,0 +1,149 @@
+/************************************************
+
+  range.c -
+
+  $Author: matz $
+  $Date: 1994/06/17 14:23:50 $
+  created at: Thu Aug 19 17:46:47 JST 1993
+
+  Copyright (C) 1994 Yukihiro Matsumoto
+
+************************************************/
+
+#include "ruby.h"
+
+VALUE M_Comparable;
+VALUE C_Range;
+
+static ID next, eq;
+
+VALUE
+range_new(class, start, end)
+    VALUE class, start, end;
+{
+    VALUE obj;
+
+    if (!obj_is_kind_of(start, M_Comparable) || TYPE(start) != TYPE(end)) {
+	Fail("bad value for range");
+    }
+
+    obj = obj_alloc(class);
+
+    rb_iv_set(obj, "start", start);
+    rb_iv_set(obj, "end", end);
+
+    return obj;
+}
+
+static VALUE
+Frng_match(rng, obj)
+    VALUE rng, obj;
+{
+    VALUE beg, end;
+
+    beg = rb_iv_get(rng, "start");
+    end = rb_iv_get(rng, "end");
+
+    if (FIXNUM_P(beg) && FIXNUM_P(obj)) {
+	if (FIX2INT(beg) <= FIX2INT(obj) && FIX2INT(obj) <= FIX2INT(end)) {
+	    return TRUE;
+	}
+	return FALSE;
+    }
+    else {
+	if (rb_funcall(beg, rb_intern("<="), 1, obj) &&
+	    rb_funcall(end, rb_intern(">="), 1, obj)) {
+	    return TRUE;
+	}
+	return FALSE;
+    }
+}
+
+static VALUE
+Frng_each(obj)
+    VALUE obj;
+{
+    VALUE b, e, current;
+
+    b = rb_iv_get(obj, "start");
+    e = rb_iv_get(obj, "end");
+
+    if (FIXNUM_P(b)) {		/* fixnum is a special case(for performance) */
+	int beg, end, i;
+
+	beg = FIX2INT(b);
+	end = FIX2INT(e);
+
+	for (i=beg; i<=end; i++) {
+	    rb_yield(INT2FIX(i));
+	}
+    }
+    else {
+	GC_LINK;
+	GC_PRO3(current, b);
+	for (;;) {
+	    rb_yield(current);
+	    if (rb_funcall(current, eq, 1, e)) break;
+	    current = rb_funcall(current, next, 0);
+	}
+	GC_UNLINK;
+    }
+
+    return Qnil;
+}
+
+static VALUE
+Frng_start(obj)
+    VALUE obj;
+{
+    VALUE b;
+
+    b = rb_iv_get(obj, "start");
+    return b;
+}
+
+static VALUE
+Frng_end(obj)
+    VALUE obj;
+{
+    VALUE e;
+
+    e = rb_iv_get(obj, "end");
+    return e;
+}
+
+static VALUE
+Frng_to_s(obj)
+    VALUE obj;
+{
+    int beg, end;
+    VALUE fmt, str, args[4];
+    
+
+    beg = rb_iv_get(obj, "start");
+    end = rb_iv_get(obj, "end");
+
+    GC_LINK;
+    GC_PRO3(fmt, str_new2("%d..%d"));
+    args[0] = obj; args[1] = fmt; args[2]= beg; args[3] = end;
+    str = Fsprintf(4, args);
+    GC_UNLINK;
+
+    return str;
+}
+
+extern VALUE M_Enumerable;
+
+Init_Range()
+{
+    C_Range = rb_define_class("Range", C_Object);
+    rb_include_module(C_Range, M_Enumerable);
+    rb_define_method(C_Range, "=~", Frng_match, 1);
+    rb_define_method(C_Range, "each", Frng_each, 0);
+    rb_define_method(C_Range, "start", Frng_start, 0);
+    rb_define_method(C_Range, "end", Frng_end, 0);
+    rb_define_method(C_Range, "to_s", Frng_to_s, 0);
+
+    eq = rb_intern("==");
+    next = rb_intern("next");
+}