Just a small idea, haven't really thought it fully through yet:

Since D has no zero-terminated strings, a character constant is basically the same as a string constant: 'a' and "a" are basically the same.

This opens up the possibility of using ' and " similar to javascript (or python for that matter), being able to mix the two: 'blah "var"' would be the same as the current "blah \"var\"".

While writing this the multi byte character constants come to mind. I do code similar to this in some C++ prog:

long c = (long&)file_extension;
switch (c)
{
case 'gepj':// jpeg
case 'gpj'://jpg
case 'agt'://tga
    // it's an image file
}

I'll still post this though, out of curiousity for the thoughts of the group.

L.

Lionello Lunesu wrote:

> Since D has no zero-terminated strings, a character constant is basically the same as a string constant: 'a' and "a" are basically the same.

D has length-prefixed strings instead, so I don't think that's correct ?


You can switch on strings in D, though...
http://www.digitalmars.com/d/statement.html#switch

--anders

"Anders F Björklund" <afb@algonet.se> wrote in message news:dnmcnb$rob$1@digitaldaemon.com...
> Lionello Lunesu wrote:
>
>> Since D has no zero-terminated strings, a character constant is basically the same as a string constant: 'a' and "a" are basically the same.
>
> D has length-prefixed strings instead, so I don't think that's correct ?

Well, ok, the array has a pointer to the actual value together with the
length:
char[1] b = "a"; //points to an 'a' in memory, paired with length 1

Whereas in C "a" and 'a' would have nothing in common: the former being a pointer to {97,0} and the latter being just the value 97. In D it's no longer to think of "a" as 'a pointer to a string', eventhough arrays contain a pointer to the string. I think of "a" as being a collection of characters, this one having only 'a'. Is a collection with only 'a' different from just 'a'? How is a char[1] different from a char?

> You can switch on strings in D, though... http://www.digitalmars.com/d/statement.html#switch

Which makes the strange (and not portable) switch construct in my original post obsolete!

L.

Lionello Lunesu wrote:

> Whereas in C "a" and 'a' would have nothing in common: the former being a pointer to {97,0} and the latter being just the value 97.

Pretty much in common, yes ? i.e. char[0] == char

> In D it's no longer to think of "a" as 'a pointer to a string',
> eventhough arrays contain a pointer to the string. I think of "a" as
> being a collection of characters, this one having only 'a'. Is a
> collection with only 'a' different from just 'a'?

Yes. One is a collection, the other is an item. :-)

> How is a char[1] different from a char?

It isn't.

But null-terminated arrays and length-prefixed arrays are
also very similar. Don't get me wrong, I also like D's
"code unit" arrays better than C's "character" arrays...
But they are not really *that* different from eachother ?


And you can use raw D strings for things with double-quotes:
`blah "var"`

The only downside being that in shell scripts and other
languages, the backticks means to escape to a sub-process...

--anders

Lionello Lunesu wrote:
> Just a small idea, haven't really thought it fully through yet:
> 
> Since D has no zero-terminated strings, a character constant is basically the same as a string constant: 'a' and "a" are basically the same.

Well it's not, as been shown in another post.

> 
> This opens up the possibility of using ' and " similar to javascript (or python for that matter), being able to mix the two: 'blah "var"' would be the same as the current "blah \"var\"".

in D, you can use
`blah "quote" etc`
(that is not the single quote ' it's the thing in the ~ button)

> 
> While writing this the multi byte character constants come to mind. I do code similar to this in some C++ prog:
> 
> long c = (long&)file_extension;
> switch (c)
> {
> case 'gepj':// jpeg
> case 'gpj'://jpg
> case 'agt'://tga
>     // it's an image file
> }

You can do switch on strings in D

> And you can use raw D strings for things with double-quotes: `blah "var"`

THAT I didn't know :-) Thanks for pointing it out.

L.

Hasan Aljudy wrote:
<snip>
> in D, you can use
> `blah "quote" etc`
> (that is not the single quote ' it's the thing in the ~ button)
<snip>

Have you checked that Lionello's keyboard is exactly the same as yours?

Stewart.

-- 
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GCS/M d- s:- C++@ a->--- UB@ P+ L E@ W++@ N+++ o K-@ w++@ O? M V? PS- PE- Y? PGP- t- 5? X? R b DI? D G e++>++++ h-- r-- !y
------END GEEK CODE BLOCK------

My e-mail is valid but not my primary mailbox.  Please keep replies on the 'group where everyone may benefit.

Stewart Gordon wrote:

>> (that is not the single quote ' it's the thing in the ~ button)
> 
> Have you checked that Lionello's keyboard is exactly the same as yours?

On my keyboard, it (`) is right next to the backspace key.

And I don't have a ~ key either... Just us non-US weirdos. :-)

--anders

PS.
Backticks are still dumb to use for the raw strings, regardless...
(since they're used elsewhere to run commands. But it's too late)

Anders F Björklund wrote:
<snip>
> Backticks are still dumb to use for the raw strings, regardless...
> (since they're used elsewhere to run commands. But it's too late)

It shouldn't be surprising that different languages use the same symbol to mean different things.  Just to name a few:

^: bitwise XOR in C(++), D, etc.  Exponentiation in BASIC, Excel, etc. Beginning of line or 'not' in regexp.  Statement separator in 4DOS.

$: string variable marker in BASIC.  Scalar variable marker in Perl and Unix shell scripts.  End of array in D.  Mingle operator in INTERCAL.

-: subtraction in most languages.  Just another character to use in variable names in COBOL.

#: preprocessor directive in C(++).  Comment in Perl, Unix shell scripts , make and Maple.  Double precision (?) variable marker in some BASICs.

{}: block statement in C(++), D, etc.  Comment in Pascal.

Stewart.

-- 
-----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GCS/M d- s:- C++@ a->--- UB@ P+ L E@ W++@ N+++ o K-@ w++@ O? M V? PS- PE- Y? PGP- t- 5? X? R b DI? D G e++>++++ h-- r-- !y
------END GEEK CODE BLOCK------

My e-mail is valid but not my primary mailbox.  Please keep replies on the 'group where everyone may benefit.

Stewart Gordon wrote:

>> Backticks are still dumb to use for the raw strings, regardless...
>> (since they're used elsewhere to run commands. But it's too late)
> 
> It shouldn't be surprising that different languages use the same symbol to mean different things.  Just to name a few:
[...]

Nope, just that this particular one has me confused every single time.

Then again it's used once in a blue moon so it's not really a problem.

--anders