"&&" and "||" in ruby statements (not if-stmts)

and_or_in_stmts_in_ruby

"&&" and "||" in ruby statements (not if-stmts):

stmt1 && stmt2
returns the first falsey result, or if no falsey's found, returns the last truthy result
ex:
'hello' && 'bye'
=> 'bye'
'hello' && false
=> false
false && 'hello'
=> false
nil && false && 'hello'
=> nil
'hello' && false && nil && 'bye'
=> false

=======================================================================

stmt1 || stmt2
returns the first truthy result, or if no truthy's found, returns the last falsey result
ex:
'hello' || 'bye'
=> 'hello'
'hello' || false
=> 'hello'
false || 'hello'
=> 'hello'
nil || false || 'hello'
=> 'hello'
false || nil
=> nil
nil || false
=> false

=======================================================================

In summary, if falsey's break &&, and if truthy's break ||:
If breakers found, stop there, and return the result at that point.
If NO breakers found, continue executing until the end, and then return the last result.

So, how's this useful?
Well, we can use a chaining of && and || to rewrite some if-stmts, for example:
if x > 5
  puts "greater"
else
  puts "smaller"
end

You can rewrite this as:
puts x>5 && "greater" || "smaller"

Done! easy breezy short form.

Mind blowing, huh?

A word of caution here is to pay attention when mixing &&'s and ||'s to use parantheses to make sure precedence is evaluated correctly.