I'd like to hear your suggestions. The file is kind of C-code like (but it isn't - it's actually an SVF JTAG Boundary scan file) and looks like this

// comments
some code;
more code;
// more comments
some very long
long long code;
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You can't set the input delimeter unless you know more than you've told us about comment lines.

I'd do something like:

my $full_line = '';
while ( my $line = <FH> )
{
    chomp $line;
    next if substr( $line, 0, 2 ) eq '//';
    $full_line .= " $line"; # space wanted? your call!
    next unless substr( $line, -1, 1 ) eq ';';

    #do something with $full_line
    print "$full_line\n";

    $full_line = '';
}
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Update: replace the $full_line .= line with

    $full_line .= $full_line eq '' ? $line : " $line";
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Update^2: I should have said this has been tested and produced the following with your sample data:

some code;
more code;
some very long long long code;
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Something like this would do it:

my $line = '';
while( <$fh> ) {
    next if m[^//];
    $line .= $_;
    if( $line =~ m[;\Z]m ) {
        ## process line or push ta a array
    }
}
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---

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

First of all: ++. Then (I wanted to /msg you, but it resulted to be longer than expected, so:)

$ perl -le 'open FOO, "file.txt"; print length $_ for (<FOO>);'
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Ok, they're just ten lines so it doesn't make a difference, but we recommend people all the time not to slurp files in all at once if possible and since we're talking about oneliners anyway, I would rewrite them like thus:

$ perl -le 'print "A" x (9000 + $_) for 1..10' > file.txt

$ perl -lpe '$_=length' file.txt
9001
9002
9003
9004
9005
9006
9007
9008
9009
9010
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