Ruby Array find first object

Question

Am I missing something in the Array documentation   I have an array which contains up to one object satisfying a certain criterion   I d like to efficiently find that object   The best idea I have from the docs is this   candidates   my array select    e  e satisfies condition    found it   candidates first if  candidates empty    But I am unsatisfied for two reasons    That select made me traverse the whole array  even though we could have bailed after the first hit  I needed a line of code  with a condition  to flatten the candidates      Both operations are wasteful with foreknowledge that there s 0 or 1 satisfying objects   What I d like is something like   array find first block    which returns nil or the first object for which the block evaluates to true  ending the traversal at that object   Must I write this myself   All those other great methods in Array make me think it s there and I m just not seeing it

User · Accepted Answer

Either I don t understand your question  or Enumerable find is the thing you were looking for

User · Answer

use array detect method if you wanted to return first value where block returns true   1 2 3 11 34  detect  amp  even      gt  2  OR   1 2 3 11 34  detect  i  i even      gt  2   If you wanted to return all values where block returns true then use select   1 2 3 11 34  select  amp  even       gt   2  34

User · Answer

Do you need the object itself or do you just need to know if there is an object that satisfies  If the former then yes  use find   found object   my array find    e  e satisfies condition      otherwise you can use any   found it   my array any      e  e satisfies condition      The latter will bail with  true  when it finds one that satisfies the condition  The former will do the same  but return the object

User · Answer

Guess you just missed the find method in the docs   my array find   e  e satisfies condition

[ruby] Ruby Array find_first object?

Examples related to ruby

Examples related to arrays

Examples related to performance

Examples related to find