Issue #9251 has been updated by shyouhei (Shyouhei Urabe).


When you want to use it in while loop your supposition is not that concrete.


  while ! line = gets do
     ....
  end


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Bug #9251: ! operator has lower precedence than = in an assignment expression
https://bugs.ruby-lang.org/issues/9251#change-43688

Author: rits (First Last)
Status: Open
Priority: Normal
Assignee: 
Category: 
Target version: 
ruby -v: ruby 2.0.0p353 (2013-11-22 revision 43784) [i686-linux]
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN


irb(main):001:0> !a = 1
(irb):1: warning: found = in conditional, should be ==
=> false
irb(main):002:0> a
=> 1

! is supposed to have higher precedence than =, so !a = 1 should be (!a) = 1, and thus an error, not !(a = 1) 



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