String Literal Docs

[Ellery Newcomer]

On 06/19/2010 03:12 PM, Alix Pexton wrote:
> I've been sketching some grammar diagrams for D2.0, a little like those
> on JSON.org, and of course I didn't get far before I ran into something
> odd.
>
> In the section of www.digitalmars.com/d/2.0/lex.html on string literals,
> the productions imply that the [c|w|d] "postfix" is allowed on Wysiwyg,
> DoubleQuote and Hex strings and not on either Delimited or Token
> strings, which didn't make a lot of sense to me, so I tested it with DMD
> (v2.046, win)...
>
> ---
>
> import std.stdio;
>
> void main(){
> auto t1 = "double quote"d; // OK
> auto t2 = `back tick`d; // OK
> auto t3 = x"dead beef"; // postfix not allowed on hexstrings!
> auto t4 = q"<delimited/>"d;// OK
> auto t5 = q{if}d; // OK
>
> writefln("all literals A-OK!");
> }
>
> ---
>
> This makes sense to me, HexStrings with wide chars would have made my
> brain scream ><


http://d.puremagic.com/issues/show_bug.cgi?id=4351


but I'm not so sure about the hex string one. I think you just gave it 
invalid unicode. E.g., this compiles fine:

auto w = x"1e1d 1e1f"w;

on dmd 2.047

but what it results in is pretty screwy.

>
> So, to correct the documentation, the "postfix" needs to be removed from
> HexString and added to DelimitedString and TokenString.
>
> I tried to see if this was already reporded in the bug tracker but
> couldn't see anything close.
>
> On a slightly quieter note, there is also a spare underscore in the
> definition of HexidecimalDigit as it "extends" DecimalDigit which
> already has an underscore.
>
> I also noticed a bug in the tracker related to initial underscores in
> float literals, if the diagrams start getting to puzzling I might look
> into that ^^

What what?

>
> A...
>
> PS, my copy of tDPL is in the post, yay!