Not sure I explained what I'm trying to achieve.

I'm looking for something that actually deletes the line instead of not rendering the line.

The background is I need to use this syntax #define with_auth on the top of my source code to actually default the value of with_auth to true, else if I use the with_auth parameters in the #if directive, it will always be evaluated to false. Default value assignment in template.json is useless there, c# conditional directive doesn't use it during design time and only runtime of the template.

example:

#define with_auth 
using Microsoft.Extensions.Hosting;
#if (with_auth)
using Microsoft.AspNetCore.Hosting;
#endif

With the replace command the final render will be like this if with_auth is true.

{empty line here} 
using Microsoft.Extensions.Hosting;
using Microsoft.AspNetCore.Hosting;

I can get away without using the syntax #define with_auth by negating it and using no_auth instead but this will resort to double negation and is very confusing for my user.

example:

using Microsoft.Extensions.Hosting;
#if (!no_auth)
using Microsoft.AspNetCore.Hosting;
#endif