http://d.puremagic.com/issues/show_bug.cgi?id=1814

           Summary: DMD/GDC does not prevent typedef violations
           Product: D
           Version: unspecified
          Platform: All
        OS/Version: All
            Status: NEW
          Keywords: accepts-invalid
          Severity: major
          Priority: P2
         Component: DMD
        AssignedTo: bugzilla@digitalmars.com
        ReportedBy: default_357-line@yahoo.de


The spec says the following about typedefs:

"A typedef or enum can be implicitly converted to its base type, but going the other way requires an explicit conversion."

Why, then, does the following work (on the most recent DMD and GDC)?

import std.stdio;
typedef int Foo;
void test(Foo foo) { }
void main() { test(3); /*ILLEGAL!*/ Foo f = cast(Foo) 2; writefln(f+3); /*ALSO
ILLEGAL*/ }

This basically makes typedef no better than alias.
Looking forward to a fix,

 --downs


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http://d.puremagic.com/issues/show_bug.cgi?id=1814





------- Comment #1 from default_357-line@yahoo.de  2008-02-03 12:06 -------
(In reply to comment #0)
> The spec says the following about typedefs:
> 
> "A typedef or enum can be implicitly converted to its base type, but going the other way requires an explicit conversion."
> 
> Why, then, does the following work (on the most recent DMD and GDC)?
> 
> import std.stdio;
> typedef int Foo;
> void test(Foo foo) { }
> void main() { test(3); /*ILLEGAL!*/ Foo f = cast(Foo) 2; writefln(f+3); /*ALSO
> ILLEGAL*/ }

Ignore the second one, please, I understand what happens. The first one is still wrong, though.
>  --downs
> 

 --downs :)


-- 

http://d.puremagic.com/issues/show_bug.cgi?id=1814


bugzilla@digitalmars.com changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |INVALID




------- Comment #2 from bugzilla@digitalmars.com  2008-03-05 00:37 -------
It turns out that disallowing:
    typedef int Foo;
    Foo f;
    f = 3;
is very onerous. It will require inserting casts everywhere a literal is used.
So implicitly converting an integer literal to a typedef is allowed. What is
not allowed is:
    int i = 3;
    f = i;
I'll update the documentation to clarify this.


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