Received on the -comments list.
> Begin forwarded message:
>
> From: Victor Nazarov <asviraspossi...@gmail.com>
> Subject: String reboot proposal
> Date: April 16, 2019 at 10:19:06 PM EDT
> To: amber-spec-comme...@openjdk.java.net
>
> I want to propose one more design vector for enhanced string literals that
> I haven't seen before
>
> Basically, I propose two extensions to get to multiline literals with
> incidental white space handling.
>
> Extension1: allow sequences of string literals to denote a single
> concatenated literal
> Extension2: allow string literals that spans from an opening token till the
> end of a line
>
> Let's start with an example:
>
> String j = ""
> + "public static void " + name + "(String... args) {\n"
> + " System.out.println(\"Hello,\\t\" +
> String.join(args));\n"
> + "}\n";
>
> Extension1: allow sequence of string literals to denote concatenated literal
>
> With this extension we can get rid of plus operators, like this:
>
> String j = ""
> "public static void " + name + "(String... args) {\n"
> " System.out.println(\"Hello,\\t\" + String.join(args));\n"
> "}\n";
>
> This feature is not so alien, it is present in C language.
> It may seem not worth it, but I think it can be worth it in combination
> with second extension.
>
> Extension2: allow string literals that spans from an opening token till the
> end of a line.
>
> String s = "hello\n";
>
> to be written as
>
> String s =
> """hello
> ;
>
> Tripple quotes in this case start a string literal which ends at an end of
> line.
>
> Having these two extensions, we can rewrite our example as:
>
> String j =
> "public static void " + name + """(String... args) {
> """ System.out.println("Hello,\\t" + String.join(args));
> """}
> ;
>
> Other examples:
>
> String sql =
> """SELECT name
> """FROM user
> """WHERE id = ? and role = 'ADMIN'
> ;
>
> String json =
> """{
> """ "login": "john",
> """ "id": 123.
> """}
> ;
>
> String html =
> """<div class="active">
> """ <span class="title">Hello, World</span>
> """</div>
> ;
>
> With this style we can't just copy and past snippets of foreign code into a
> string literal, but
> all we need is to prefix every line with tripple quotes.
> This style is analogues to source code comments handling by programmers,
> so, I think, it's familiar enough.
>
> // TODO: rewrite this method
> // using new guava API
>
> Automatic prefixing of comments is already present in every IDE and is
> simple enough to implement by hand, like
>
> | sed 's/^/"""/g'
>
> Rawness can be added to such string literals independently in orthogonal
> way:
>
> String regex = \"a(bc)+\s+(de|kg)?"\;
>
> String j =
> \"public static void "\ + name + \"""(String... args) {
> \""" System.out.println("Hello,\t" + String.join(args));
> \"""}
> ;
>
> The problem I see is interoperability between simple string literals and
> "line sting literals": we can't easily align them vertically.
> But may be this problem is more easily solvable than magical incidental
> whitespace handling.
>
> --
> Victor Nazarov
