Changed the behavior of mrb_range_beg_len(); close #3411

The new API is:

int mrb_range_beg_len(mrb, range, &beg, &len, len, trunc)

The new argument `trunc` is a boolean value that specifies
whether the function truncates the range. The new return value
is an integer instead of a boolean, that is:

 0: not a range
 1: range with proper edges
 2: out of range

To get the old behavior, you have to rewrite:

  mrb_range_beg_len(mrb, range, &beg, &len, len)

to:

  mrn_range_beg_len(mrb, range, &beg, &len, len, TRUE) == 1

[Breaking Change]

1 files changed, 1 insertions, 1 deletions

diff --git a/include/mruby/range.h b/include/mruby/range.h
index fb602b3f3..41e4f1254 100644
--- a/include/mruby/range.h
+++ b/include/mruby/range.h
@@ -41,7 +41,7 @@ MRB_API struct RRange* mrb_range_ptr(mrb_state *mrb, mrb_value v);
  */
 MRB_API mrb_value mrb_range_new(mrb_state *mrb, mrb_value start, mrb_value end, mrb_bool exclude);
 
-MRB_API mrb_bool mrb_range_beg_len(mrb_state *mrb, mrb_value range, mrb_int *begp, mrb_int *lenp, mrb_int len);
+MRB_API int mrb_range_beg_len(mrb_state *mrb, mrb_value range, mrb_int *begp, mrb_int *lenp, mrb_int len, mrb_bool trunc);
 mrb_value mrb_get_values_at(mrb_state *mrb, mrb_value obj, mrb_int olen, mrb_int argc, const mrb_value *argv, mrb_value (*func)(mrb_state*, mrb_value, mrb_int));
 
 MRB_END_DECL