davido has the best idea but if you want to use a regex you can use something like: 
my $list = 
"RcvChar
checkeof
SerialOutputString
SerialOutputString
SerialOutputString
GetFile
ChksumByteByByte
GetChksum
SerialOutputString
SerialOutputString";
while ($list =~ s/(\b\w+\b)(.*?)\s+\1\b/$1$2/s) {};
print $list;

[download]
outputs : 
RcvChar
checkeof
SerialOutputString
GetFile
ChksumByteByByte
GetChksum

[download]

--

flounder

In reply to Re: Removing duplicates from list by flounder99
in thread Removing duplicates from list by Levan

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