Re: Writing unix-style filters

I think your solution is correct, but your actual implementation could be more succinct.

This:

@files = map { -f $_ ? $_ : () } @ARGV;
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could (and arguably should) be written as

@files = grep { -f $_ } @ARGV;
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This:

    while ( <> ) {
        chomp;
        push @files, $_;
    }
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could be written as

    chomp( @files = <> );
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though you might have a concern if the file list is huge, relative to your available memory. :-)

Ultimately, the whole chunk of code could be written as

    chomp( @files = @ARGV ? grep { -f $_ } @ARGV : <> );
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A word spoken in Mind will reach its own level, in the objective world, by its own weight

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Re^2: Writing unix-style filters by bart (Canon) on Apr 11, 2007 at 11:18 UTC
`chomp( @files = @ARGV ? grep { -f $_ } @ARGV : <> );` This chomps after you do the file test, with the newline not yet removed. So, it will just produce an empty array, when reading the file list from the input, because `-f $_` will always return false.	[reply] [d/l] [select]
Re^3: Writing unix-style filters by jdporter (Paladin) on Apr 11, 2007 at 15:38 UTC
No; actually, it will not, because the `-f` test operator here is not being applied to the strings which are returned from the `<>`. Perhaps it should be; in which case you'd have a very good point. `chomp( @files = @ARGV ? @ARGV : <> ); @files = grep { -f $_ } @files;` [download] A word spoken in Mind will reach its own level, in the objective world, by its own weight	[reply] [d/l] [select]