Assisting: both errors appear to refer to a lack of content in $_ the default variable set by various operations. $_ is explicitly mentioned in your line 3 and implicit in your line 2.

Inserting a print $_\n before the chomp will probably confirm or rebut my hypothesis. Then, if I'm on target, you can read up to find what you expected to set the default.


Spirit of the Monastery


In reply to Re^3: How to format fasta file by ww
in thread How to format fasta file by andyBio

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