3 ms·

Is this: def fibonacci(max=Float::INFINITY) # ... while i < max # ... end end better than this: def fibonacci(max=nil)

by hk__2 13y ago

Is this: def fibonacci(max=Float::INFINITY) # ... while i < max # ... end end better than this: def fibonacci(max=nil) # ... while max && i < max # ... end end ? (genuine question)

Xylakant 13y ago
yes. The first one does what it's intended to, the second plain fails :) Voice-of-Evening:~ $ irb irb(main):001:0> max=Float::INFINITY => Infinity irb(main):002:0> i = 0 => 0 irb(main):003:0> i < max => true irb(main):004:0> max = nil => nil irb(main):005:0> max && i < max => nil The second version will only provide any result when a specific max value was given, while the first one will loop into infinity.
- hk__2 13y ago
  Yes, I messed up. I meant `!max && i < max`.
  - Xylakant 13y ago
    Then the code is functionally equivalent, but the first version is much more readable. As pointed out on the parent comment, the first version does one test less, a minor performance benefit.
nilved 13y ago
What you meant is `while !max || max < i`, but the answer is the same: the former will perform better because it only makes one comparison for each iteration of the loop. The latter needs to additionally check the existence of max.