Allow "here-document"/verbatim string to consume first (and possibly last) line-feed/white-space.

[NeilMacMullen]

It's a small thing but it's annoying when my verbatim strings look like this....

const string Message = @"some aligned text:
      - which is really hard to align properly with the second word in the first line
      - and where the closing quote must be on the same line to avoid a trailing linefeed.";

What I'd really like to be able to write is some variation of

const string Message = @-"
some aligned text:
      - which is now easy to align properly with the second word in the first line
      - and where the closing quote can be on the following line for cosmetic reasons
      - (making it much easier to add new text to the end of the string in future)
";
    

As a suggestion, perhaps a magic token such as '-' after the '@' can be used to request the compiler performs a Trim on the string?

[NeilMacMullen]

#4013 seems to have a similar motivation and https://developercommunity.visualstudio.com/idea/602807/indent-multi-line-verbatim-strings.html is also related.

However, this proposal seems considerably easier to implement and has far less ambiguity; white-space and indentation are don't have to be calculated/visually adjusted according to the position of the first line since the left border is always used, It's simply a matter of applying a Trim operation to the entire string.