Ref http://digitalmars.com/d/2.0/lex.html

What are some possible use cases for delimited strings? What is solved by having this in the language?

> Ref http://digitalmars.com/d/2.0/lex.html
> 
> What are some possible use cases for delimited strings? What is solved by having this in the language?

It's probably so that you can still use characters that require escaping in the string without having to escape " everywhere. WYSIWYGS don't allow for escaping characters, which can be annoying periodically. Still, delimited strings do seem a bit funny to me, and I don't think that I've ever used them. Presumably, they solved some problem fairly nicely, but the only thing that I can think of is that they still allow for characters that require escaping but don't force you to escape ", which could be very useful in strings with lots of "s and other characters that need escaping.

- Jonathan M Davis

On 10/04/2011 17:51, Jonathan M Davis wrote:
>> Ref http://digitalmars.com/d/2.0/lex.html
>>
>> What are some possible use cases for delimited strings?
>> What is solved by having this in the language?
>
> It's probably so that you can still use characters that require escaping in
> the string without having to escape " everywhere. WYSIWYGS don't allow for
> escaping characters, which can be annoying periodically. Still, delimited
> strings do seem a bit funny to me, and I don't think that I've ever used them.
> Presumably, they solved some problem fairly nicely, but the only thing that I
> can think of is that they still allow for characters that require escaping but
> don't force you to escape ", which could be very useful in strings with lots
> of "s and other characters that need escaping.
>
> - Jonathan M Davis


DelimitedString:
	q" Delimiter WysiwygCharacters MatchingDelimiter "

Therefore you can choose you delimiter, which as you say might be " Also it looks like you can't use any escapes, because it says WysiwygCharacters above.

and further down:

Wysiwyg Strings

Wysiwyg quoted strings are enclosed by r" and ". All characters between the r" and " are part of the string except for EndOfLine which is regarded as a single \n character. There are no escape sequences inside r" ":

I take that to mean that you can't use escapes in DelimitedStrings, either.

This would be quite useful for regex, for example.

> On 10/04/2011 17:51, Jonathan M Davis wrote:
> >> Ref http://digitalmars.com/d/2.0/lex.html
> >> 
> >> What are some possible use cases for delimited strings? What is solved by having this in the language?
> > 
> > It's probably so that you can still use characters that require escaping in the string without having to escape " everywhere. WYSIWYGS don't allow for escaping characters, which can be annoying periodically. Still, delimited strings do seem a bit funny to me, and I don't think that I've ever used them. Presumably, they solved some problem fairly nicely, but the only thing that I can think of is that they still allow for characters that require escaping but don't force you to escape ", which could be very useful in strings with lots of "s and other characters that need escaping.
> > 
> > - Jonathan M Davis
> 
> DelimitedString:
> 	q" Delimiter WysiwygCharacters MatchingDelimiter "
> 
> Therefore you can choose you delimiter, which as you say might be " Also it looks like you can't use any escapes, because it says WysiwygCharacters above.
> 
> and further down:
> 
> Wysiwyg Strings
> 
> Wysiwyg quoted strings are enclosed by r" and ". All characters between the r" and " are part of the string except for EndOfLine which is regarded as a single \n character. There are no escape sequences inside r" ":
> 
> I take that to mean that you can't use escapes in DelimitedStrings, either.
> 
> This would be quite useful for regex, for example.

I didn't read carefully enough then. I thought that delimited strings allowed for escaped characters. If they don't, then I really don't understand why they exist. WYSIWYG strings already do that for you. All you have to do is use backticks instead of double quotes. Maybe backticks aren't on all types of keyboards? If so, that might explain the addition, but other than that, the only thing that I can think of is if you want a WYSIWYG string with lots of backticks in it.

- Jonathan M Davis

Are we forgetting the fact that using delimited strings allows us to have syntax highlighting in editors?

E.g.:

void stringParser(string str)()
{
    mixin(str);
}

void main()
{
    stringParser!(q{
        int x = 1;
        int y = 2;

        writefln("%s %s", x, y);
    });
}

This is a huge benefit over having everything highlighted in one solid color as a string.

On 10.04.2011 21:17, Andrej Mitrovic wrote:
> Are we forgetting the fact that using delimited strings allows us to
> have syntax highlighting in editors?
>
> E.g.:
>
> void stringParser(string str)()
> {
>      mixin(str);
> }
>
> void main()
> {
>      stringParser!(q{
>          int x = 1;
>          int y = 2;
>
>          writefln("%s %s", x, y);
>      });
> }
>
> This is a huge benefit over having everything highlighted in one solid
> color as a string.

That's token strings. This is delimited strings:
q"(foo(xxx))"   // "foo(xxx)"
q"[foo{]"       // "foo{"

Hmm..

Well then, those I've never seen used before. :)

On 4/10/11 11:03 AM, simendsjo wrote:
> Ref http://digitalmars.com/d/2.0/lex.html
>
> What are some possible use cases for delimited strings?
> What is solved by having this in the language?

Readability.

auto s = "This is 'something' that \"could\" have been made easier to read";

auto t = q"[This is 'something' that "could" have been made easier to read]";

(although I don't like that you have to type two chars after the q. In ruby you'd write

%q(This is 'something' that "could have been made easier to read)

)

> On 4/10/11 11:03 AM, simendsjo wrote:
> > Ref http://digitalmars.com/d/2.0/lex.html
> > 
> > What are some possible use cases for delimited strings? What is solved by having this in the language?
> 
> Readability.
> 
> auto s = "This is 'something' that \"could\" have been made easier to read";
> 
> auto t = q"[This is 'something' that "could" have been made easier to read]";
> 
> (although I don't like that you have to type two chars after the q. In ruby you'd write
> 
> %q(This is 'something' that "could have been made easier to read)
> 
> )

WYSIWYG strings already give you that with everything but backticks. So, other than strings with both backticks and quotes in them, I don't see much point to delimited strings. The string that you gave could have been done with

auto t = `This is 'something' that "could" have been made easier to read`;

If that had been `something instead of 'something, _then_ the delimited string becomes useful, but given how rarely backticks are needed, it does seem rather odd to have delimited strings just for that. So, I definitely have to wonder why they exist.

- Jonathan M Davis

On 4/10/11 5:51 PM, Jonathan M Davis wrote:
>> On 4/10/11 11:03 AM, simendsjo wrote:
>>> Ref http://digitalmars.com/d/2.0/lex.html
>>>
>>> What are some possible use cases for delimited strings?
>>> What is solved by having this in the language?
>>
>> Readability.
>>
>> auto s = "This is 'something' that \"could\" have been made easier to
>> read";
>>
>> auto t = q"[This is 'something' that "could" have been made easier to
>> read]";
>>
>> (although I don't like that you have to type two chars after the q. In
>> ruby you'd write
>>
>> %q(This is 'something' that "could have been made easier to read)
>>
>> )
>
> WYSIWYG strings already give you that with everything but backticks. So, other
> than strings with both backticks and quotes in them, I don't see much point to
> delimited strings. The string that you gave could have been done with
>
> auto t = `This is 'something' that "could" have been made easier to read`;
>
> If that had been `something instead of 'something, _then_ the delimited string
> becomes useful, but given how rarely backticks are needed, it does seem rather
> odd to have delimited strings just for that. So, I definitely have to wonder
> why they exist.
>
> - Jonathan M Davis

true