Something along these lines? 
m{
  .*    # match as late as possible
  (
     ^abc$ # the abc
     .*?   # everything up to
     ^def$ # the def
  )
}smx

[download]

Untested, and will be confused if there are mulitple def lines. In that case it helps to tokenize the input first (for example reading line by line)

In reply to Re: How do I match the closest of repeated strings? by moritz
in thread How do I match the closest of repeated strings? by Anonymous Monk

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