Personally, I'd rather prefix with `\\` than have to postfix with `\n`. The `\\` is automatically prepended when I enter a newline in my editor after I start a multiline string, much like editors have done for C-style multiline comments for years.

Snippet from my shader compiler tests (the `\` vs `/` in the paths in params and output is intentional, when compiled it will generate escape errors so I'm prodded to make everything `/`):

    test "shader_root_gen" {
        const expected =
            \\// Generated file!
            \\
            \\pub const @"spriteszzz" = opaque {
            \\    pub const @"quadsprite" = @import("src\spriteszzz/quadsprite.glsl");
            \\};
            \\
            \\pub const @"sprites" = opaque {
            \\    pub const @"universalsprite" = @import("src\sprites/universalsprite.glsl");
            \\};
            \\
            \\pub const @"simpleshader" = @import("src/simpleshader.glsl");
            \\
        ;

        const cmdline =
            \\--prefix src -o testfile.zig src\spriteszzz/quadsprite.glsl src\sprites/universalsprite.glsl src/simpleshader.glsl
        ;

        var args_iter = std.mem.tokenizeScalar(u8, cmdline, ' ');
        const params = try Params.parseFromCmdLineArgs(&args_iter);

        var buffer: [expected.len * 2]u8 = undefined;
        var stream = std.io.fixedBufferStream(buffer[0..]);
        try generateSource(stream.writer().any(), params.input_files.items, params.prefix);
        const actual = stream.getWritten();

        try std.testing.expectEqualSlices(u8, expected, actual);
    }