From: "NAKAMURA, Hiroshi" <nakahiro@...>
Date: 2003-12-24T10:30:28+09:00
Subject: Re: Ruby 1.8.1 preview4

Hi, Dennis,

Last 2 point.

> From: "Dennis Ranke" <exoticorn@epost.de>
> Newsgroups: comp.lang.ruby
> Sent: Wednesday, December 24, 2003 3:36 AM

> > [1, 2, 31, 32; floating point]
> >
> >>    1) Failure:
> >> test_SOAPDouble(SOAP::TestSOAP) [./soap/test_basetype.rb:257]:
> >> <"-0"> expected but was
> >> <"+0">.
> >
> > How does this dump?
> > $ ruby -e 'a = -0.0; p (1 / a > 0.0)'
> >
> > expecting false..
> 
> irb(main):002:0> VERSION
> => "1.8.1"
> irb(main):001:0> a=-0.0
> => 0.0
> irb(main):002:0> 1 / a > 0.0
> => true
> irb(main):003:0> 1 / a
> => Infinity

On your ruby, "-0.0" shoud be interpreted 0.0.  Gotoken hacked and
told me that if I expect "-0.0" to be interpreted as negative zero
in ruby,
  "echo 'main(){double a = 0; a = -a; puts(1/a < 0 ? "n" : "p");}' |
    gcc -xc - && ./a.out"
must dump "n".  May be "p" on your system?

I can use "-1.0 / (1.0 / 0.0)" instead of "-0.0" for soap4r test.
How does this dump?

$ ruby -e 'p(-1.0 / (1.0 / 0.0))'

> >>    2) Failure:
> >> test_SOAPFloat(SOAP::TestSOAP)
> >>      [./soap/test_basetype.rb:161:in `test_SOAPFloat'
> >>       ./soap/test_basetype.rb:160:in `each'
> >>       ./soap/test_basetype.rb:160:in `test_SOAPFloat']:
> >> <1.4e-45> expected but was
> >> <0.0>.
> >
> > Hmm...
> 
> ok, my theory about single-precision floats was probably wrong:
> irb(main):009:0> 1.0/2**256
> => 8.63616855509444e-78
> 
> So as long as SOAP doesn't convert between different float 
> representations, i have no idea where this error comes from.

"float" in XML Schema Datatypes (and SOAP) is a single float.
Ruby's is double.  So I try to "narrow"? the given double float
to single with

  d = given_double # e.g. 1.4e-45
  f = (/\A\0*\z/ =~ [d].pack("f")) ? 0.0 : d
  sprintf("%.10g", f) # use this as a value of "float"

Maybe I misunderstand something...

$ ruby -e 'p([1.4e-45].pack("f"))'

?

> > [3-9, 28-30; socket]
> >>    3) Error:
> >> test_charset(SOAP::TestStreamHandler):
> >> SocketError: getaddrinfo: Temporary failure in name resolution
> >
> > $ ruby -rsocket -e 'p Socket.getaddrinfo("localhost", "http")'
> >
> > Same error?
> 
> Yes, and "unknown host" with "ping localhost", so i added localhost to my 
> hosts file, which got rid of those errors... ;)

:)  Thanks.

There shoudl be some architecture/settings where "localhost" is
not defined.  But I don't know portable way to test server/client.

Regards,
// NaHi