Effective Ruby

effective_ruby.md

Effective Ruby

#1 (Almost) Everything is true

• Every value is true except false and nil.
• The number zero is true in Ruby.
• Use the nil? method to differentiate between false and nil.

#2 All objects could be nil

• Coerce nil objects into the expected type (eg use to_i and to_s).
• Array#compact/Hash#compact removes all nil elements.
• Array#dig/Hash#dig returns nil if any intermediate step is nil.

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#4 Constants are mutable

• Always freeze constants to prevent them form being mutated (eg TIMEOUT = 5.freeze).

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#7 Different behaviours of super

• When you override a method from inheritance hierarchy the super keyword can be used to call the overriden method.
• Using super with no arguments and parentheses is equivalent to passing it all of the arguments that were given to the enclosing method.
• If you want to use super without passing the overriden method any arguments, you must use empty parentheses (eg super()).

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References

• https://github.com/pjones/effrb
• https://www.effectiveruby.com/#code
• https://www.amazon.com/Effective-Ruby-Specific-Software-Development/dp/0133846970