Dear Monks,

This problem has been bothering me for some time. It feels like it should be possible, but I don't know where to begin.
I have some text data - a csv file for example. I have a subroutine that can parse csv data, say csvparse(). How can I make csvparse() smart so that it can accept csv data from a string passed as a scalar, from a filehandle, or from a file without slurping in the entire file (except in the scalar case, of course) and without making three separate subs - one for each data type? Is this possible?
Here is some stumbling in the dark... 
#!/usr/bin/perl -w
use strict;
use CGI;

{
# case 1 - a file
my $file = "csvfile.csv";
my %parseddata = csvparse($file);
}

{
# case 2 - a filehandle
my $uploadedfile = param('uploadfile');
my %parseddata = csvparse($uploadedfile);
}

{
# case 3 - a scalar
my $csvdata = 'first,middle,last,phone,email';
my %parseddata = csvparse($csvdata);
}

# so how can I avoid having three separate csv parsing subs?
# Once it can get at the data, the parsing is the same for all 3 cases
+!

sub csvparse {
   my $data = $_[0];

   if (ref($data) eq 'SCALAR') {
      for (split(/\n/,$data)) {
         # parse...
      }
   } elsif (-f "$data") {
      open(DATA, "$data") or die("Noooo!\n");
      while (<DATA>) {
         # parse...
      }
      close(DATA);
   } elsif () { # detect filehandle???
   }
}

[download]

yuck.
Thanks

In reply to Handling different data types of the same data by blahblah

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