This is probably laughably elementary, but feel free to ridicule anyway ...

I need to examine numerous collections of items (strings), and if specific items (the same 6 items throughout, only 3 shown below) are missing from a collection then they must be added (but added only if missing). Each collection has from five to thirty items in it.

Something like this ungainly semi-pseudocode: 

for each collection {
  $have-apple   = 0;
  $have-orange  = 0;
  $have-pear    = 0;

  #examine about 30 items:
  for each item {
    if( $item eq "apple" )  { $have-apple  = 1; }
    if( $item eq "orange" ) { $have-orange = 1; }
    if( $item eq "pear" )   { $have-pear   = 1; }
  }

  # then, when all items examined
  unless( $have-apple )  { add apple; }
  unless( $have-orange ) { add orange; }
  unless( $have-pear )   { add pear; }
}

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My bones tell me that perl can do this much more elegantly ... please suggest how, kind brothers

In reply to are they all there? by anadem

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