From: Heesob Park <phasis@...>
Date: 2009-03-26T15:48:46+09:00
Subject: Re: Operator precedence of exponentiation (**) and complement (~)

2009/3/26 Andrew Savige <ajsavige@yahoo.com.au>:
>
> The operator precedence table at:
>
>  http://phrogz.net/ProgrammingRuby/language.html#table_18.4
>
> states that the exponentiation operator (**) has higher precedence than
> the complement operator (~). Ditto for operator precedence in Python.
>
> Yet the following program:
>
>  x = ~2**3
>  print x, "\n"      # prints -27 in Ruby; prints -9 in Python
>
> surprised me by printing -27 (I am using ruby 1.8.6).
>
> BTW, the following program prints -9 in both Ruby and Python:
>
>  x = ~(2**3)
>  print x, "\n"
>
> Is this a Ruby bug?
>
According to the japanese reference
manual(http://doc.loveruby.net/refm/api/view/spec/operator),
this is not a bug.
I guess this precedence change was made on ruby 1.8.0

C:\work\ruby168\bin>ruby -v -e 'p ~2**3'
ruby 1.6.8 (2002-12-24) [i586-mswin32]
-9

C:\work\ruby180\bin>ruby -v -e 'p ~2**3'
ruby 1.8.0 (2003-08-04) [i386-mswin32]
-27


Regards,

Park Heesob