Not the same thing. When this is the 1st 5 lines of a script, A displays line 2, and both B and C report the $scriptline is 4 as if line 3 doesn't exist. But D shows in editor as line 5, and that's what $scriptline says.
alias linetest {
echo -a A $scriptline
echo -a B $scriptline $&
echo -a C $scriptline test
echo -a D $scriptline
}