I concur with haukex that you should make a SSCCE to demonstrate/research your issue. Something very simple like:

# 1210614.pl
package MyClass {
    use Moose;
    has FileName => (is => 'rw', isa => 'Str', writer => 'SetFileName'
+);
    sub SetFileName {
        my $self = shift;
        my $arg = shift;
        warn "I am here with $arg";
    }
};

package main {
    my $obj = MyClass->new;
    $obj->SetFileName('/foo/bar');
};
[download]

This will show you the error clearly. Output:

$ perl 1210614.pl
You are overwriting a locally defined method (SetFileName) with an acc
+essor ...
[download]

As you can see this is not what specifying a custom writer does. As far as I understand it, specifying a custom writer property for an attribute simply changes the name of the writer from the default.

# 1210614-1.pl
package MyClass {
    use Moose;
    has FileName => (is => 'rw', isa => 'Str', writer => 'SetFileName'
+);
};

package main {
    my $obj = MyClass->new;
    $obj->SetFileName('/foo/bar');
    warn $obj->FileName;
};
[download]

Output:

$ perl 1210614-1.pl
/foo/bar at 1210614-1.pl line 9.
[download]

For what you are doing your code should use a custom type check, or a coercion, or a trigger instead.

# 1210614-2.pl
package MyClass {
    use Moose;
    has FileName => (is => 'rw', isa => 'Str', trigger => \&SetFileNam
+e);
    sub SetFileName {
        my $self = shift;
        my $arg = shift;
        warn "I am here with $arg";
    }
};

package main {
    my $obj = MyClass->new;
    $obj->SetFileName('/foo/bar');
};
[download]

Output:

$ perl 1210614-2.pl
I am here with /foo/bar at 1210614-2.pl line 7.
[download]

Hope this helps!

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.