ruby - Why is my code entering a string when I explicitly convert into an int, ONLY for one specific output? -

this i'm working on right now.

here code (feel free critique it, , please do).

def order_weight(weights)     weightslist = weights.split(" ")     def convert(weight)       weight.split("").reduce{|sum,n| sum.to_i + n.to_i}     end     weightsconv = weightslist.map {|weight| convert(weight)}     weightslist.sort_by{|a| [weightsconv[weightslist.index(a)],a]}.join(" ") end 

this works on everything except following input string: order_weight("3 16 9 38 95 1131268 49455 347464 59544965313 496636983114762 85246814996697")

in case (by printing), see first 3 entries in weightsconv corrupted "3", "7", "9". else stays same. solved adding .map{|n| n.to_i} @ end of line 7. don't understand why necessary, since i'm converting inside previous block. goes wrong inside one input? ruby bug?

no, it's bug.

from enumerable#reduce documentation:

if not explicitly specify initial value memo, first element of collection used initial value of memo.

that's reason you've written sum.to_i because sum string in case. if collection has 1 element (such ["3"]) there no need invoke block because documentation says return value first element (which "3"). code can fixed explicitly setting initial value (to 0):

a = ["3"] = a.reduce { |sum, n| puts 'called'; sum + n.to_i } # no output p # => "3" = a.reduce(0) { |sum, n| puts 'called'; sum + n.to_i } # => called p # => 3 

if want code reviewed, try code review stack exchange. biggest code smell definition of method inside method. use lambda or rid of instead.