[fpc-devel] Tests in Delphi XE3 regarding Type Helpers

[Marco van de Voort]

In our previous episode, Sven Barth said:
> For tthlperr2.pas it would have been interesting to see if the same 
> error is reported if a helper is in scope, but the method is invalid... 
> could you please repeat that test with a string helper and a string 
> constant? 

tthlperr2.pas(15) Error: E2003 Undeclared identifier: 'DoTest2'

>Or change the type of the int helper to "uint8" which seems to 
> have helped in the tthlpsize.pas test...

Only for unsigned constants. I tried, and the results are the same dotest2.

Even with the unsigned value. Only if I change dotest2 to dotest1 I get the
operator not applicable. So somehow the method name has prio over the
literal type mismatch
 
> > D:\testing\rechelp>dcc32 tthlpminus.pas
> > Embarcadero Delphi for Win32 compiler version 24.0
> > Copyright (c) 1983,2012 Embarcadero Technologies, Inc.
> > tthlpminus.pas(14) Error: E2018 Record, object or class type required
> > tthlpminus.pas(15) Error: E2018 Record, object or class type required
> > tthlpminus.pas(17)
> >
> > 1. Typecasting the "42" literals to integer works
> > 2. changing record helper type to "int64" doesn't.
> > 3. Changing to smaller types (int8,int16) doesn't help.
> > 4. changing to uint8 works for the "42" one, not for the "-42" one.
> Ok... so Delphi does use the minimum required size for the constant. 

For unsigned ones yes.

> Good. Does "int8" help for the "-42"? What if you change it to 
> "(-42).DoTest"?

Then it passes for the signed (int8) type. So it seems there is no helper
that will accept both positive and negative literals.

> > D:\testing\rechelp>dcc32 tthlpself.pas
> > Embarcadero Delphi for Win32 compiler version 24.0
> > Copyright (c) 1983,2012 Embarcadero Technologies, Inc.
> > tthlpself.pas(36)
> > 37 lines, 0.09 seconds, 18816 bytes code, 13240 bytes data.
> >
> > D:\testing\rechelp>tthlpself
> > -> throws RTE 105
> 
> It seems that I forgot a "{$apptype console}" :)

42
21
Type Helper
Hello Type Helper World

> > D:\testing\rechelp>dcc32 tthlpsize.pas
> > Embarcadero Delphi for Win32 compiler version 24.0
> > Copyright (c) 1983,2012 Embarcadero Technologies, Inc.
> > tthlpsize.pas(24) Error: E2003 Undeclared identifier: 'Short'
> > tthlpsize.pas(78) Error: E2015 Operator not applicable to this operand type
> > tthlpsize.pas(80) Error: E2015 Operator not applicable to this operand type
> > tthlpsize.pas(82) Error: E2015 Operator not applicable to this operand type
> > tthlpsize.pas(84) Error: E2015 Operator not applicable to this operand type
> > tthlpsize.pas(87)
> >
> > The first is easily fixable by changing short (which probably should have
> > been shortint) to int16.
> The introduction of the (U)IntXX types was one of the best things I 
> remember (and luckily we already have them in FPC as well :) ), as I 
> always forget how the smaller types are named... -.-

Why do you think I added them when I found out? :-)  I never could either.
(specially smallint and shortint)
 
> > The remaining errors are the negative values. I didn't find a solution for
> > them with tthlpminus
> So the hexadecimal values work correctly?

Yes

> What if you here also try the 
> suggestion "(negativevalue).DoTest"? You might also want to add a 
> "{$apptype console}" here.

Strange results. All compile except (-1)

Input:

 Writeln(0, #9, 0.DoTest);
//  Writeln(-1, #9, (-1).DoTest);
  Writeln($ABCD, #9, $ABCD.DoTest);
  Writeln(-32987, #9, (-32987).DoTest);
  Writeln(2345678, #9, 2345678.DoTest);
  Writeln(-2345678, #9, (-2345678).DoTest);
  Writeln($1234567887654321, #9, $1234567887654321.DoTest);
  Writeln(-9876543211234, #9, (-9876543211234).DoTest);
  Writeln(9876543211234, #9, 9876543211234.DoTest);

 Output:
 

0       Byte
43981   Word
-32987  LongInt
2345678 LongInt
-2345678        LongInt
1311768467139281697     Int64
-9876543211234  Int64
9876543211234   Int64

... which seems to have a bias for signed types that I didn't see
in earlier tests.

I played a bit with the minus one value, and got an IE:

Writeln(-129, #9, (-129).DoTest);

caused:

D:\testing\rechelp>dcc32 tthlpsize.pas
Embarcadero Delphi for Win32 compiler version 24.0
Copyright (c) 1983,2012 Embarcadero Technologies, Inc.
tthlpsize.pas(78) Fatal: F2084 Internal Error: SY3502

> Otherwise: Thank you so far. :)

As soon as it is finished, you go back to generics? :-)