[RUBY] Be absolutely careful when putting the result of and / or in a variable!

[x = true and false] does not work as expected

true and false # => false
false and true # => false
true and true # => true
false and false # => false

true && false # => false
false && true # => false
true && true # => true
false && false # => false

x = true and false # => false
p x # => true !!!!!!!!!!
x = false and true # => false
p x # => false
x = true and true # => true
p x # => true
x = false and false # => false
p x # => false

x = true && false # => false
p x # => false
x = false && true # => false
p x # => false
x = true && true # => true
p x # => true
x = false && false # => false
p x # => false



Has a lower priority than =, so with x = true and false

  1. x = true
  2. true and false (results are discarded)

Will occur, and x will not become false.


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