Method: List#fetch

Defined in:
ext/list/list.c

#fetch(*args) ⇒ Object 



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# File 'ext/list/list.c', line 955

static VALUE
list_fetch(int argc, VALUE *argv, VALUE self)
{
	VALUE pos, ifnone;
	long block_given;
	long idx;
	list_t *ptr;

	Data_Get_Struct(self, list_t, ptr);
	rb_scan_args(argc, argv, "11", &pos, &ifnone);
	block_given = rb_block_given_p();
	if (block_given && argc == 2) {
		rb_warn("block supersedes default value argument");
	}
	idx = NUM2LONG(pos);

	if (idx < 0) {
		idx += LIST_LEN(self);
	}
	if (idx < 0 || LIST_LEN(self) <= idx) {
		if (block_given) return rb_yield(pos);
		if (argc == 1) {
			rb_raise(rb_eIndexError, "index %ld outside of array bounds: %ld...%ld",
					idx - (idx < 0 ? LIST_LEN(self) : 0), -LIST_LEN(self), LIST_LEN(self));
		}
		return ifnone;
	}
	return list_entry(self, idx);
}