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Comment by cubicle67 | Hacker News Reader

I'm not familiar with LINQ, but is that roughly equivalent to

    grains.select{|g|
      g.is_a?(Salt) && g.value.blank?
    }.sort{|a,b|
      a.irrelevance <=> b.irrelevance
    }.first

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Ruby tip: Instead of .sort you can use .sort_by.

    grains.select{|g|
      g.is_a?(Salt) && g.value.nil?
    }.sort_by(&:irrelevance).first

Edit: Changed from blank? to nil? since that is probably closer to nothing in C#.

thanks. I've been writing Ruby for a few years now and I never knew about sort_by. Looks like is works in 1.8 too, but without the &: syntax

    sort_by{|g|g.irrelevance}

source: http://www.ruby-doc.org/core-1.9.2/Enumerable.html#method-i-...

I actually believe the &:symbol syntax was added in 1.8.7 since I am 100% positive we use that in our codebase which still has not been ported to 1.9.

  $ ruby -e 'puts VERSION; p ["10", "2", "3"].sort_by(&:to_i)'
  1.8.7
  ["2", "3", "10"]

Rails adds it too, even if your version of Ruby does not support it. Yay monkeypatching!

EDIT: said duck typing first. It's too early for thinking.

var saltGrains = new List<Salt>();

foreach (var g in grains) {

    if (g.TypeOf() == "Salt" && g.Value == nothing)

        saltGrains.Add(g);

}

saltGrains.sort(m => m.Value.irellevance);

return saltGrains.First();

or something.

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