Dear Monks,

Why does this bit of code give me problems? 

$infile = "outfile.txt";
open (INFILE, "$infile");

$out_b = "outfile_b.txt";
open (OUT_B, "+>>$out_b");

while(<INFILE>){   
    print "here\n";
    
    if ($_ =~ /^(.{1,50})\t{0,50}(.{0,50})\t{0,1}(.{0,50})\t{0,1}(.{0,
+50})\t{0,1}(.{0,50})\t{0,1}(.{0,50})/){
    
    print "here_B\n";

    $gene_id = $1;
    if ($2 = /.{1,50}/){ (@alternative_ids, $2)};
    if ($3 = /.{1,50}/){ (@alternative_ids, $3)};
    if ($4 = /.{1,50}/){ (@alternative_ids, $4)};
    if ($5 = /.{1,50}/){ (@alternative_ids, $5)};
    if ($6 = /.{1,50}/){ (@alternative_ids, $6)};
    if ($7 = /.{1,50}/){ (@alternative_ids, $7)};
    if ($8 = /.{1,50}/){ (@alternative_ids, $8)};
           if ($9 = /.{1,50}/){ (@alternative_ids, $9)};
    print @alternative_id; 
    foreach (@alternative_ids){
        
        $alternative_id = $_;
        print OUT_B "$gene_id\t$alternative_id\n"; 
        
    }
    undef @alternative_ids;
    }
}

[download]
where infile is something like: 
YAL069W
YAL069W    Yal069wp
YAL068C
YAL068C    Yal068cp
SEO1    YAL067C
SEO1    Seo1p
YAL066W
YAL066W    Yal066wp
YAL065C
YAL064W-B
YAL064W-B    Yal064w-bp
YAL064C-A
YAL064C-A    Yal064c-ap
YAL064W

[download]
I get the error message: 

Modification of a read-only value attempted at extract_notes_B.pl line
+ 149, <INFILE> line 2.

[download]

In reply to File handle problems by matth

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