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POThe most idiomatic way to iterate through a Ruby array, exiting when an arbitrary condition met?
 

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  1. POThe most idiomatic way to iterate through a Ruby array, exiting when an arbitrary condition met?
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    <p>I want to iterate through an array, each element of which is an array of two integers (e.g. `[3,5]'); for each of these elements, I want to calculate the sum of the two integers, exiting the loop when any of these sums exceeds a certain arbitrary value. The source array is quite large, and I will likely find the desired value near the beginning, so looping through all of the unneeded elements is not a good option.</p> <p>I have written three loops to do this, all of which produce the desired result. My question is: which is more idiomatic Ruby? Or--better yet--is there a better way? I try not to use non-local loop variables in, but <code>break</code> statements look kind of hackish to my (admittedly novice) eye.</p> <pre><code># Loop A pairs.each do |pair| pair_sum = pair.inject(:+) arr1 &lt;&lt; pair_sum break if pair_sum &gt; arr2.max end #Loop B - (just A condensed) pairs.each { |pair| arr1.last &lt;= arr2.max ? arr1 &lt;&lt; pair.inject(:+) : break } #Loop C i = 0 pair_sum = 0 begin pair_sum = pairs[i].inject(:+) arr1 &lt;&lt; pair_sum i += 1 end until pair_sum &gt; arr2.max </code></pre> <p>A similar question was asked at <a href="https://stackoverflow.com/questions/1568288/escaping-the-each-iteration-early-in-ruby/1568445#1568445">escaping the .each { } iteration early in Ruby</a>, but the responses were essentially that, while using <code>.each</code> or <code>.each_with_index</code> and exiting with <code>break</code> when the target index was reached would work, <code>.take(num_elements).each</code> is more idiomatic. In my situation, however, I don't know in advance how many elements I'll have to iterate through, presenting me with what appears to be a boundary case.</p> <p>This is from a project Euler-type problem I've already solved, btw. Just wondering about the community-preferred syntax. Thanks in advance for your valuable time.</p>
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    1. CODo you want to print the value for which sum > 6 (say)? or only to test?
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      1. POThe most idiomatic way to iterate through a Ruby array, exiting when an arbitrary condition met?
      1. USArup Rakshit
    2. COI am pushing the sums of each pair below a certain threshold value to an array for further processing. The only thing printed by the script is a triplet of integers, and that is several steps down the road from here.
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    3. COAre the values already sorted?
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      1. USPatrick Oscity
 

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