[ruby-dev:48650] [ruby-trunk - Bug #10393] [Open] String#start_with?の1.9.x非互換バグ

Issue #10393 has been reported by Hideyuki Matsuyama.

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Bug #10393: String#start_with?=E3=81=AE1.9.x=E9=9D=9E=E4=BA=92=E6=8F=9B=E3=
=83=90=E3=82=B0
https://bugs.ruby-lang.org/issues/10393

* Author: Hideyuki Matsuyama
* Status: Open
* Priority: Normal
* Assignee:=20
* Category:=20
* Target version:=20
* ruby -v: ruby 2.1.3p242 (2014-09-19 revision 47630) [x86_64-darwin13.0]
* Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN
----------------------------------------
~~~
$ ruby -v
ruby 1.9.3p547 (2014-05-14 revision 45962) [x86_64-darwin13.4.0]
$ irb
> 'foo'.start_with? nil
 =3D> false=20
~~~
~~~
$ ruby -v
ruby 2.1.3p242 (2014-09-19 revision 47630) [x86_64-darwin13.0]
$ irb
> 'foo'.start_with? nil
TypeError: no implicit conversion of nil into String
~~~

=E3=83=90=E3=83=BC=E3=82=B8=E3=83=A7=E3=83=B31.9=E7=B3=BB=E3=81=A8=E3=81=AE=
=E4=BA=92=E6=8F=9B=E6=80=A7=E3=82=92=E4=BF=9D=E3=81=A4=E3=81=9F=E3=82=81=E3=
=80=81=E7=B5=90=E6=9E=9C=E3=81=8Cfalse=E3=81=AB=E3=81=AA=E3=82=8B=E3=81=93=
=E3=81=A8=E3=82=92=E6=9C=9F=E5=BE=85=E3=81=97=E3=81=BE=E3=81=99=E3=80=82



--=20
https://bugs.ruby-lang.org/