ruby - (a && b) versus (a and b) -

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given :

a=true b=false

why can :

puts [a && b, || b]  #[false, true]

but not

puts [a , b, or b]

syntax error, unexpected keyword_and, expecting ']' puts [a , b, or b]

apparently, operator precedence comma higher "and" lower &&.

putting parenthesis around elements works:

[(a , b), (a or b)]

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