I use the following to successfully find my ANCHOR (regex pattern) and replace it with my param-value inside a file (filepath).

```
sed -i $"/$ANCHOR/i \\$PARAMVALSEDINS" "$FILEPATH"

```

What I need is for when my ANCHOR is '' (empty) to instead match my EOF and do the replacement there.

So I imagine doing something like this:

> 
> if ANCHOR='' then ANCHOR='$EOF' so that SED successfully finds the EOF
>  and proceeds with the replacement.
> 
> 
> 

Can this be done? Couldn't find anything specific except for this:

```
sed -i -e "\$aPARAMVALSEDINS" "$FILEPATH"

```

However, this does not involve the ANCHOR variable and I will implement it if my question is not possible to be answered.

PS. Of course it could be possible to use another method altogether. Maybe there is a way to do this with another command that DOES facilitate regex matching AND EOF matching within the regex area? 
e.g.
another -i $"/$ANCHOR/i \$PARAMVALSEDINS" "$FILEPATH"
where if $ANCHOR can be a match for EOF

Thanks