Or you could actually use all. 

all { $res[$_ - 1]{end_date} eq $res[$_]{start_date} } 1 .. $#res

[download]

Or if you want to know which ones are "bad" so you can output a message for each of them: 

map { $res[$_ - 1] }
   grep { $res[$_ - 1]{end_date} ne $res[$_]{start_date} }
      1..$#res

[download]

In reply to Re^2: A proper name for is_sorted function that can check more than just sorting order? by ikegami
in thread A proper name for is_sorted function that can check more than just sorting order? by Dallaylaen

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