setTypeInfo???

[Denis Koroskin]

On Sun, 31 Aug 2008 01:45:55 +0400, bearophile <bearophileHUGS at lycos.com>  
wrote:

> dsimcha Wrote:
>
>> I've noticed something strange with the setTypeInfo() function in gc.d.  
>> Ran
>> into it trying to write some custom allocation functions for dynamic  
>> arrays.
>> writefln(typeid(uint).flags);  //Returns 0.
>> writefln(typeid(float).flags);  //Returns 0.
>> writefln(typeid(uint*).flags);  //Returns 1.
>> writefln(typeid(void*).flags);  //Returns 1.
>
> Ah, for that purpose I have used the following monster (take a look at  
> my last post too  
> http://www.digitalmars.com/webnews/newsgroups.php?art_group=digitalmars.D&article_id=75811
> ):
>
>
> import std.traits: FieldTypeTuple;
>
> template IsType(T, Types...) {
>     // Original idea by Burton Radons, modified
>     static if (Types.length == 0)
>         const bool IsType = false;
>     else
>         const bool IsType = is(T == Types[0]) || IsType!(T, Types[1 ..  
> $]);
> }
>
> template ArrayType1(T: T[]) {
>     alias T ArrayType1;
> }
>
> template IsReferenceType(Types...) {
>     static if (Types.length == 0) {
>         const bool IsReferenceType = false;
>     } else static if (Types.length == 1) {
>         static if (IsType!(Types[0], bool, byte, ubyte, short, ushort,  
> int, uint,
>                            long, ulong, float, double, real, ifloat,  
> idouble,
>                            ireal, cfloat, cdouble, creal, char, dchar,  
> wchar) ) {
>             const bool IsReferenceType = false;
>         } else static if ( is(Types[0] == struct) ) {
>             const bool IsReferenceType =  
> IsReferenceType!(FieldTypeTuple!(Types[0]));
>         } else static if (IsStaticArray!(Types[0])) {
>             const bool IsReferenceType =  
> IsReferenceType!(ArrayType1!(Types[0]));
>         } else
>             const bool IsReferenceType = true;
>     } else
>         const bool IsReferenceType = IsReferenceType!(Types[0]) |
>                                      IsReferenceType!(Types[1 .. $]);
> } // end IsReferenceType!()
>
>
> template IsArray(T) {
>     const bool IsArray = is(typeof(T.length)) && is(typeof(T.sort)) &&
>                          is(typeof(T.reverse)) && is(typeof(T.dup));
> }
>
> template IsDynamicArray(T) {
>     // Adapted from the module tango.core.Traits, (C) 2005-2006 Sean  
> Kelly, BSD style licence
>     const bool IsDynamicArray = is( typeof(T.init[0])[] == T );
> }
>
> template IsStaticArray(T) {
>     const bool IsStaticArray = IsArray!(T) && (!IsDynamicArray!(T));
> }
>
> Bye,
> bearophile


Looks like my message class is a static array:

class Message
{
     this(char[] message) { this.message = message; }

     size_t length() { return message.length; }
     void sort() { message.sort(); }
     void reverse() { message.reverse(); }
     Message dup() { return new Message(message.dup()); }
     char[] toString() { return message; }

     private char[] message;
}

assert(IsStaticArray!(Message) == false); // fails