i want to match a pattern ignoring the white spaces at the end of each word. can anyone help ?

suppose the string is 

my $x = "set manager logport [<0-10000>]
  set manager secondary ip A.B.C.D
  set mgmtport auto
  set mgmtport speed (10|100) duplex (full|half)
  set portsettletime <0-300>
  set sensor gateway A.B.C.D
  set sensor ip A.B.C.D E.F.G.H";

[download]
now i want to do a pattern match for 
my $y = set mgmtport speed (10|100) duplex (full|half)

if ($x=~ /$y\s+/ig)
{
}

[download]
if i do the above this thing is not working

2006-09-18 Retitled by holli, as per Monastery guidelines
Original title: 'pattern matching'

In reply to How Do I Skip Spaces At The End of Words Using A Regex? by phemal

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