digitalmars.D.bugs - Deprecated cast bug

Ilya Zaitseff (6/6) Jul 25 2004 void main()

Walter (4/10) Jul 26 2004 Such parsing ambiguities are why C style casts are deprecated . (It i...

Derek Parnell (8/20) Jul 26 2004 Does this mean the we can never have the construct ...

Walter (6/22) Jul 26 2004 is

Stewart Gordon (9/22) Jul 27 2004 I personally don't see much difficulty in trying to parse it as an

Walter (6/23) Jul 27 2004 never

Jarrett Billingsley (2/2) Jul 26 2004 if the "unary plus" operator didn't exist, we wouldn't have this problem...

Walter (4/6) Jul 26 2004 ;)

Arcane Jill (3/8) Jul 27 2004 Cool. What would you call it though? opDoNothing()? opTrivial()?

Walter (4/12) Jul 27 2004 problem

James McComb (6/9) Jul 27 2004 Just a feeling... UnaryAdd feels a bit "technical" for me.

Arcane Jill (6/7) Jul 27 2004 Well, actually, we'd still have the problem with unary minus.

Jarrett Billingsley (1/2) Jul 27 2004 agh forgot about that one..
Ivan Senji (11/19) Aug 06 2004 ;)

"Ilya Zaitseff" <sark7 mail333.com> writes:

void main()
{
   int i, j;
   int k = (i)+j;
}

[dmd 0.96] outputs: C style cast deprecated, use cast(i)(j)

Jul 25 2004

"Walter" <newshound digitalmars.com> writes:

"Ilya Zaitseff" <sark7 mail333.com> wrote in message
news:opsbpwecsuaaezs2 ilya.tec.amursk.ru...
 void main()
 {
    int i, j;
    int k = (i)+j;
 }

 [dmd 0.96] outputs: C style cast deprecated, use cast(i)(j)

Such parsing ambiguities are why C style casts are deprecated <g>. (It is
parsed as (i)(+j), i.e. the + is seen as the unary plus operator.)

Jul 26 2004

Derek Parnell <derek psych.ward> writes:

On Mon, 26 Jul 2004 10:07:28 -0700, Walter wrote:

 "Ilya Zaitseff" <sark7 mail333.com> wrote in message
 news:opsbpwecsuaaezs2 ilya.tec.amursk.ru...
 void main()
 {
    int i, j;
    int k = (i)+j;
 }

 [dmd 0.96] outputs: C style cast deprecated, use cast(i)(j)

 
 Such parsing ambiguities are why C style casts are deprecated <g>. (It is
 parsed as (i)(+j), i.e. the + is seen as the unary plus operator.)

Does this mean the we can never have the construct ...

   '(' <identifier> ')' <operand> <expression>

in D?

-- 
Derek
Melbourne, Australia
27/Jul/04 11:33:09 AM

Jul 26 2004

"Walter" <newshound digitalmars.com> writes:

"Derek Parnell" <derek psych.ward> wrote in message
news:ce4bgd$1lir$1 digitaldaemon.com...
 On Mon, 26 Jul 2004 10:07:28 -0700, Walter wrote:

 "Ilya Zaitseff" <sark7 mail333.com> wrote in message
 news:opsbpwecsuaaezs2 ilya.tec.amursk.ru...
 void main()
 {
    int i, j;
    int k = (i)+j;
 }

 [dmd 0.96] outputs: C style cast deprecated, use cast(i)(j)

 Such parsing ambiguities are why C style casts are deprecated <g>. (It


is
 parsed as (i)(+j), i.e. the + is seen as the unary plus operator.)

 Does this mean the we can never have the construct ...

    '(' <identifier> ')' <operand> <expression>

 in D?

You will once I take out C style casts completely. But unlike C, you never
need to enclose an identifier in redundant parens, so it isn't a problem.
(It's needed in C because of macro arguments.)

Jul 26 2004

Stewart Gordon <smjg_1998 yahoo.com> writes:

Walter wrote:

 "Ilya Zaitseff" <sark7 mail333.com> wrote in message
 news:opsbpwecsuaaezs2 ilya.tec.amursk.ru...

 void main()
 {
    int i, j;
    int k = (i)+j;
 }

 [dmd 0.96] outputs: C style cast deprecated, use cast(i)(j)




<snip>
 You will once I take out C style casts completely. But unlike C, you never
 need to enclose an identifier in redundant parens, so it isn't a problem.
 (It's needed in C because of macro arguments.)

I personally don't see much difficulty in trying to parse it as an 
AddExpression first ... but yes, getting rid of C casts is the way to go.

Stewart.

-- 
My e-mail is valid but not my primary mailbox, aside from its being the 
unfortunate victim of intensive mail-bombing at the moment.  Please keep 
replies on the 'group where everyone may benefit.

Jul 27 2004

"Walter" <newshound digitalmars.com> writes:

"Stewart Gordon" <smjg_1998 yahoo.com> wrote in message
news:ce5bgk$22f6$1 digitaldaemon.com...
 Walter wrote:

 "Ilya Zaitseff" <sark7 mail333.com> wrote in message
 news:opsbpwecsuaaezs2 ilya.tec.amursk.ru...

 void main()
 {
    int i, j;
    int k = (i)+j;
 }

 [dmd 0.96] outputs: C style cast deprecated, use cast(i)(j)




 <snip>
 You will once I take out C style casts completely. But unlike C, you


never
 need to enclose an identifier in redundant parens, so it isn't a


problem.
 (It's needed in C because of macro arguments.)

 I personally don't see much difficulty in trying to parse it as an
 AddExpression first ...

Consider (identifier). Is identifier a type, or a variable? The parser
doesn't know, as it does not do semantic analysis.

Jul 27 2004

"Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:

if the "unary plus" operator didn't exist, we wouldn't have this problem ;)

what the hell is it for anyway?  jill wants to know too.

Jul 26 2004

"Walter" <newshound digitalmars.com> writes:

"Jarrett Billingsley" <kb3ctd2 yahoo.com> wrote in message
news:ce4bnm$1lla$1 digitaldaemon.com...
 if the "unary plus" operator didn't exist, we wouldn't have this problem

;)
 what the hell is it for anyway?  jill wants to know too.

For completeness. It should be overloadable, though.

Jul 26 2004

Arcane Jill <Arcane_member pathlink.com> writes:

In article <ce4r8j$1s0a$1 digitaldaemon.com>, Walter says...

 if the "unary plus" operator didn't exist, we wouldn't have this problem

;)
 what the hell is it for anyway?  jill wants to know too.

For completeness. It should be overloadable, though.

Cool. What would you call it though? opDoNothing()? opTrivial()?

Jill :)

Jul 27 2004

"Walter" <newshound digitalmars.com> writes:

"Arcane Jill" <Arcane_member pathlink.com> wrote in message
news:ce51g7$1v8s$1 digitaldaemon.com...
 In article <ce4r8j$1s0a$1 digitaldaemon.com>, Walter says...

 if the "unary plus" operator didn't exist, we wouldn't have this



problem
;)
 what the hell is it for anyway?  jill wants to know too.

For completeness. It should be overloadable, though.

 Cool. What would you call it though? opDoNothing()? opTrivial()?

opUnaryAdd()

Jul 27 2004

James McComb <alan jamesmccomb.id.au> writes:

Walter wrote:

Cool. What would you call it though? opDoNothing()? opTrivial()?

 
 opUnaryAdd()

Just a feeling... UnaryAdd feels a bit "technical" for me.

Since +5 is positive 5, and -5 is negative 5, what do you think of:

opPositive for unary add
opNegative  for unary subtract

James McComb

Jul 27 2004

Arcane Jill <Arcane_member pathlink.com> writes:

In article <ce4bnm$1lla$1 digitaldaemon.com>, Jarrett Billingsley says...
if the "unary plus" operator didn't exist, we wouldn't have this problem ;)

Well, actually, we'd still have the problem with unary minus.

This problem will go away in time, once C-style casts change from "deprecated"
to "illegal". (But I'd still like to know what unary plus is for, given that we
can't overload it to do anything useful).

Jill

Jul 27 2004

"Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:

 Well, actually, we'd still have the problem with unary minus.

agh forgot about that one..

Jul 27 2004

"Ivan Senji" <ivan.senji public.srce.hr> writes:

"Arcane Jill" <Arcane_member pathlink.com> wrote in message
news:ce51c7$1v7j$1 digitaldaemon.com...
 In article <ce4bnm$1lla$1 digitaldaemon.com>, Jarrett Billingsley says...
if the "unary plus" operator didn't exist, we wouldn't have this problem


;)
 Well, actually, we'd still have the problem with unary minus.

 This problem will go away in time, once C-style casts change from

"deprecated"
 to "illegal". (But I'd still like to know what unary plus is for, given

that we
 can't overload it to do anything useful).

completeness!

I can write:

real x = +sin(angle)*W+cos(angle)*H;
real y = -sin(angle)*W-cos(angle)*H;

or something like that that makes sence. Now the first +
makes the difference between x and y much clearer.


 Jill

Aug 06 2004

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digitalmars.D.bugs - Deprecated cast bug