regex issues

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Dear Monks, I want to match something using a regular expression between 1 and 30 times. However, using {m,n} only allows me to match a maximum of 9 times. Does anyone know how I can do this?

Here's what i've got:


# I need to match the $4 up to ~ 30 times.
if ($ssh[0] =~ /^\s*>(\w+)\-(\w+)\-(\w+)\s+((\n\w+){1,9})/)  {
   print "$1 $2 $3 \n $4\n";
}

# this is what i'm matching:
>MWG869551-C3277-T7
CCCATCCAGTTTATGAGATCGCGCATTGATCGCCCGAGGCGGTCTA
GCCGCCACACCACTAATGTATCGCCGGCGCGCAATTGCTCTTTAATTTTCTCAAGCCCCG
GCCGCGCAGTGACAACGCCAGAGACCTTATCAGTGATGACCTTTTCGCAGCCCGCCGCCC
GTAAAGCGTCGGTTTGAAGATCCAAATTTTGTTCGATGGTCGAGACCCGCGCATAGCCAA
TCTTCATACGAGCAGTGCCCGGCCATTGAGAAAAGGAAGAAAACTCATGTTATCCTGAAA
TTCATTGCCCTAGTTTTCTTTACCGAGTAGATTTACCGGCATTCGGTAGAATTGGCAACG
TGTTGGAGATCGCGTGACCATTACC
[download]

Comment on regex issues Download Code

Replies are listed 'Best First'.
Re: regex issues by grinder (Bishop) on Jan 04, 2005 at 16:25 UTC
However, using {m,n} only allows me to match a maximum of 9 times Oh really? What version of Perl are you using? `% perl -le 'print shift()=~/^ab{20,30}$/ ? "yay" : "nay"' abb nay % perl -le 'print shift()=~/^ab{20,30}$/ ? "yay" : "nay"' abbbbbbbbbbb +bbbbbbbbb yay % perl -le 'print shift()=~/^ab{20,30}$/ ? "yay" : "nay"' abbbbbbbbbbb +bbbbbbbbbbbbbbbbbbbbbb nay` [download] Works for me... - another intruder with the mooring of the heart of the Perl	[reply] [d/l]
Re: regex issues by ikegami (Patriarch) on Jan 04, 2005 at 16:28 UTC
Do you really need to specify a max? Can't you just replace `{1,9}` with `+`? The last `\s+` needs to be `\s` (or needs to be removed) for regexp to match what you provided. `(\n\w+)` should be `(?:\n\w+)` (speeds things up a little), or maybe even `(?:\n[ACGT]+)` (for conciseness). $ssh[0] = <<'__EOI__'; >MWG869551-C3277-T7 CCCATCCAGTTTATGAGATCGCGCATTGATCGCCCGAGGCGGTCTA GCCGCCACACCACTAATGTATCGCCGGCGCGCAATTGCTCTTTAATTTTCTCAAGCCCCG GCCGCGCAGTGACAACGCCAGAGACCTTATCAGTGATGACCTTTTCGCAGCCCGCCGCCC GTAAAGCGTCGGTTTGAAGATCCAAATTTTGTTCGATGGTCGAGACCCGCGCATAGCCAA TCTTCATACGAGCAGTGCCCGGCCATTGAGAAAAGGAAGAAAACTCATGTTATCCTGAAA TTCATTGCCCTAGTTTTCTTTACCGAGTAGATTTACCGGCATTCGGTAGAATTGGCAACG TGTTGGAGATCGCGTGACCATTACC >... __EOI__ if ($ssh[0] =~ /^\s>(\w+)\-(\w+)\-(\w+)\s*((?:\n[ACGT]+)+)/) { print "$1 $2 $3 \n $4\n"; } __END__ output ====== MWG869551 C3277 T7 CCCATCCAGTTTATGAGATCGCGCATTGATCGCCCGAGGCGGTCTA GCCGCCACACCACTAATGTATCGCCGGCGCGCAATTGCTCTTTAATTTTCTCAAGCCCCG GCCGCGCAGTGACAACGCCAGAGACCTTATCAGTGATGACCTTTTCGCAGCCCGCCGCCC GTAAAGCGTCGGTTTGAAGATCCAAATTTTGTTCGATGGTCGAGACCCGCGCATAGCCAA TCTTCATACGAGCAGTGCCCGGCCATTGAGAAAAGGAAGAAAACTCATGTTATCCTGAAA TTCATTGCCCTAGTTTTCTTTACCGAGTAGATTTACCGGCATTCGGTAGAATTGGCAACG TGTTGGAGATCGCGTGACCATTACC [download]	[reply] [d/l] [select]