http://d.puremagic.com/issues/show_bug.cgi?id=7432

           Summary: dmd allows pure variables and treats pure like auto
           Product: D
           Version: unspecified
          Platform: All
        OS/Version: All
            Status: NEW
          Severity: normal
          Priority: P2
         Component: DMD
        AssignedTo: nobody@puremagic.com
        ReportedBy: jmdavisProg@gmx.com


--- Comment #0 from Jonathan M Davis <jmdavisProg@gmx.com> 2012-02-03 14:58:27 PST ---
This compiles:

void main()
{
    pure foo = "hello";
}

It should be illegal. Variables can't be pure. Even worse, pure here is treated as if it were auto.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432


Stewart Gordon <smjg@iname.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |rejects-valid
                 CC|                            |smjg@iname.com
            Summary|dmd allows pure variables   |DMD allows variables to be
                   |and treats pure like auto   |declared as pure


--- Comment #1 from Stewart Gordon <smjg@iname.com> 2012-02-12 11:42:21 PST ---
It isn't pure that is treated as auto.  What's treated as auto is the presence of any attribute (to turn it from an ExpressionStatement into a DeclarationStatement) combined with the absence of a type.  But otherwise yes.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432


Andrej Mitrovic <andrej.mitrovich@gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |andrej.mitrovich@gmail.com


--- Comment #2 from Andrej Mitrovic <andrej.mitrovich@gmail.com> 2012-10-26 17:22:02 PDT ---
The problem is there can be a pure block such as this one in object.di:

class TypeInfo_Struct : TypeInfo
{
  @safe pure nothrow
  {
    uint function(in void*)               xtoHash;
    bool function(in void*, in void*) xopEquals;
    int function(in void*, in void*)      xopCmp;
    string function(in void*)             xtoString;

    uint m_flags;  // << problem
  }
 }

I don't know whether the front-end makes any difference between declarations in attribute blocks and those who have a direct attribute in one statement. If not, it's probably not fixable without breaking code.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432


bearophile_hugs@eml.cc changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |bearophile_hugs@eml.cc


--- Comment #3 from bearophile_hugs@eml.cc 2012-10-26 17:42:12 PDT ---
(In reply to comment #2)

> I don't know whether the front-end makes any difference between declarations in attribute blocks and those who have a direct attribute in one statement. If not, it's probably not fixable without breaking code.

Moving the variable out of that block should be harmless :-) Automatic testing is there for similar purposes.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432



--- Comment #4 from Andrej Mitrovic <andrej.mitrovich@gmail.com> 2012-10-26 17:43:00 PDT ---
(In reply to comment #3)
> (In reply to comment #2)
> 
> > I don't know whether the front-end makes any difference between declarations in attribute blocks and those who have a direct attribute in one statement. If not, it's probably not fixable without breaking code.
> 
> Moving the variable out of that block should be harmless :-) Automatic testing is there for similar purposes.

Yes but there's no telling how much more code it would break.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432



--- Comment #5 from Stewart Gordon <smjg@iname.com> 2012-10-27 08:56:07 PDT ---
(In reply to comment #2)
> The problem is there can be a pure block such as this one in object.di:
<snip>
> I don't know whether the front-end makes any difference between declarations in attribute blocks and those who have a direct attribute in one statement.  If not, it's probably not fixable without breaking code.

Of course it's fixable - by changing it so that the front-end does make this difference.  See the long-debated issue 3118.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432


Maxim Fomin <maxim@maxim-fomin.ru> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |maxim@maxim-fomin.ru


--- Comment #6 from Maxim Fomin <maxim@maxim-fomin.ru> 2013-08-17 10:44:23 PDT ---
This is a feature of D - in general case any attribute is legal (except those for which there are arbitrary checks and rejections) and auto can be replaced by other attributes to launch type inference. Since pure is harmless here I think this is resolved-wontfix.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432


Temtaime <temtaime@gmail.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |temtaime@gmail.com


--- Comment #7 from Temtaime <temtaime@gmail.com> 2013-08-17 12:36:11 PDT ---
Pure variables it's strange.
D is young lang so i think it's welcome to fix the bugs and change behavior
even with breaking the code.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432



--- Comment #8 from Stewart Gordon <smjg@iname.com> 2013-08-18 09:24:53 PDT ---
(In reply to comment #6)
> This is a feature of D

According to which bit of the spec?

> - in general case any attribute is legal (except those for which there are arbitrary checks and rejections) and auto can be replaced by other attributes to launch type inference.  Since pure is harmless here I think this is resolved-wontfix.

Maybe, but it doesn't seem to me to make much sense.  If it's intended behaviour, this needs to be stated in the spec.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------

http://d.puremagic.com/issues/show_bug.cgi?id=7432



--- Comment #9 from Maxim Fomin <maxim@maxim-fomin.ru> 2013-08-18 09:35:09 PDT ---
(In reply to comment #8)
> (In reply to comment #6)
> > This is a feature of D
> 
> According to which bit of the spec?
> 
> > - in general case any attribute is legal (except those for which there are arbitrary checks and rejections) and auto can be replaced by other attributes to launch type inference.  Since pure is harmless here I think this is resolved-wontfix.
> 
> Maybe, but it doesn't seem to me to make much sense.  If it's intended behaviour, this needs to be stated in the spec.

Decl:
    StorageClasses Decl

StorageClasses:
    StorageClass
    StorageClass StorageClasses


StorageClass:
    abstract
    auto
    TypeCtor
    deprecated
    enum
    extern
    final
    nothrow
    override
    pure
    __gshared
    Property
    scope
    static
    synchronized

from Declaration page.

Am not telling that pure variables make much sense (I tried to clarity relation
between auto and type inference), the problem is follows:
1) pure int foo; is legal by spec and grammar
2) Despite of 1) dmd arbitrary rejects some wired combinations, sometimes not.
3) There are other issues in Bugzilla like "storage class X is accepted in
context Y" (but don't ask which numbers, I don't remember them now). So,
situation is totally sporadic right now and it needs comprehensive solution.
Adding one check to ban pure in variable declaration is not a solution to the
problem.

-- 
Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email
------- You are receiving this mail because: -------