my @xforms = (
    sub {
        $_[0] = $_[0] || 1;
    },
    sub {   # dummy, no transform
        $_[0];
    },
    sub {1},
    sub {
        $_[0] =~ s/foo/bar/;
        $_[0];
    },
    sub {1},
    sub {1},
    sub {1},
    sub {1},
);

while (<DATA>) {
    my @tmp = split ',';
    for (0 .. $#tmp) {
        $xforms[$_]->($tmp[$_]);
    }
    print join ',', @tmp;
}