passing parameters to function as variable

Hi -

I was wondering if anyone has tried creating a variable containing the
parameter list for a MARC method.

In the snippet below, I'm doing some cleanup on subfields of the 245,
and inserting a default subfield h for those lacking one.  I never know
which subfields I'll have, so rather than using a cumbersome series of
if...elsif...else statements, I'd construct the string I want to pass to
the new() function, and insert it once.  If any subfield doesn't exist,
the SFstring variable for that subfield is empty.

I know that the string in $subfield_list_245 contains the string I want,
from having used the print statement [1], but every run gives me the
error " Field 245 must have at least one subfield".

I've tried using the eval statement on the $subfield_list_245, and using
various quotation marks around it, but new() just doesn't recognize or
want to work with the string.

Is there a way to make this approach work?  Are the blanks I've
concatenated to the end a problem?

Or is there a more succinct way of approaching this in the first place?

Start snippet>>>>
if ( ! $subfield_245h ) {

    my $subfield_list_245 = $a_SFstring . $b_SFstring . $c_SFstring .
',h=>' . "'" . "[Electronic resource]" . "'" . $n_SFstring . $
p_SFstring;

## print $subfield_list_245;

    my $revised_245 =  MARC::Field->new('245', '',
'',$subfield_list_245);

    $record->replace_with($revised_245);


}
<<<<end snippet

Thanks for any ideas!

Merritt

[1] for my simple test record, the subfield list prints out:
a=>'Accountancy Ireland',h=>'[Electronic resource]'

Merritt Lennox
Library Management System Administrator
550A Bird Library
Syracuse University
Syracuse, NY 13244
315-443-9629
[email protected]

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