Bug #1715: Numeric#arg for NaN is Inconsistent Across Versions
http://redmine.ruby-lang.org/issues/show/1715

Author: Run Paint Run Run
Status: Open, Priority: Low
ruby -v: ruby 1.9.2dev (2009-07-01 trunk 23924) [i686-linux]

Numeric#arg gives 0 for NaN on 1.9; Pi for NaN on 1.8:

   $ ruby -v -rcomplex -e 'p (0/0.0).arg'
   ruby 1.9.2dev (2009-07-01 trunk 23924) [i686-linux]
   -e:1: warning: (...) interpreted as grouped expression
   0

   $ ruby -v -e 'p (0/0.0).arg'
   ruby 1.9.2dev (2009-07-01 trunk 23924) [i686-linux]
   -e:1: warning: (...) interpreted as grouped expression
   0

   $ ruby8 -v -rcomplex -e 'p (0/0.0).arg'
   ruby 1.8.8dev (2009-07-01) [i686-linux]
   -e:1: warning: (...) interpreted as grouped expression
   3.14159265358979


----------------------------------------
http://redmine.ruby-lang.org