Issue #9251 has been updated by rits (First Last). this exception leads to bizarre, visually difficult to parse and likely unintended legal expressions: a * -b = -c / d means a * -(b = (-c / d)) how's that better than if the precedence rules were universal so the above would mean (a * -b) = (-c / d) and thus an error in cases like these == is likely intended, so a syntax error is much better than a legal but nonsensical expression ---------------------------------------- Bug #9251: ! operator has lower precedence than = in an assignment expression https://bugs.ruby-lang.org/issues/9251#change-43709 Author: rits (First Last) Status: Feedback Priority: Low Assignee: Category: doc 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) -- http://bugs.ruby-lang.org/