You could try 

$line =~ m/0\s+(.+?)\s+SUBCASE/;
my $expr = $1;

[download]

Or 

my $expr = substr( $line, 4, 40 );

[download]

If the format is truely as fixed as it appears from your limited sample.

In reply to Re: How can I extract the expression between two key words by BrowserUk
in thread How can I extract the expression between two key words by Anonymous Monk

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