Precedence
From highest to lowest, this is the precedence table for ruby. High precedence operations happen before low precedence operations.
!, ~, unary +
**
unary -
*, /, %
+, -
<<, >>
&
|, ^
>, >=, <, <=
<=>, ==, ===, !=, =~, !~
&&
||
.., ...
?, :
modifier-rescue
=, +=, -=, etc.
defined?
not
or, and
modifier-if, modifier-unless, modifier-while, modifier-until
{ } blocks
Unary + and unary - are for +1, -1 or -(a + b).
Modifier-if, modifier-unless, etc. are for the modifier versions of those keywords. For example, this is a modifier-unless statement:
a += 1 unless a.zero?
Note that (a if b rescue c) is parsed as ((a if b) rescue c) due to reasons not related to precedence. See modifier statements.
{ ... } blocks have priority below all listed operations, but do ... end blocks have lower priority.
All other words in the precedence table above are keywords.