String Literal Docs

[Alix Pexton]

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 ><

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 ^^

A...

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