Forward Declarations

Merlin

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Forward Declarations

· Gepostet: 10.08.2010 - 14:24 Uhr · #1

@ Rolf.

In the compiler manual the following is described

Code

type TPtr = pointer; forward; // preliminary declaration
TRec1 = record
Ptr1 : TPtr;
end;
TPtr = pointer to Trec1; // main declaration

(I have removed "...")

This does not compile - I get the error "Error: Duplicate declaration".

Regards

Merlin.

p.s. I should have said that this is in the interface section of a unit.

pps Here is a work around. Maybe manual needs to be changed? It is more logical any way:

Code

type TRec1 = record; forward; // preliminary declaration
TPtr = pointer to Rec1;
TRec1 = record
Ptr1 : TPtr;
end;

This compiles OK

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Re: Forward Declarations

· Gepostet: 11.08.2010 - 21:18 Uhr · #2

Hello Merlin,

ok, the first failure is a limitation. But I'm pretty unsure what I can write into the manual to warn the user...

rolf

Merlin

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Re: Forward Declarations

· Gepostet: 12.08.2010 - 09:43 Uhr · #3

Hi Rolf.

Just give a different example, (i.e. one that compiles) such as my work-around. As long as there is a way and the example is valid I think that is fine, but there should not be an example in the manual that does not compile.

Cheers

Merlin.

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Re: Forward Declarations

· Gepostet: 12.08.2010 - 20:31 Uhr · #4

Hello Merlin,

where did you find this bad sample?

rolf

Merlin

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Re: Forward Declarations

· Gepostet: 13.08.2010 - 09:41 Uhr · #5

Hi Rolf.

It is in DocuCompiler.pdf section 4.1.17 - page 33, and then again on page 71 (I also noticed a typo, Funktion instead of Function an that page).

Regards

Merlin.

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Re: Forward Declarations

· Gepostet: 13.08.2010 - 13:20 Uhr · #6

Hello Merlin,

thank you.

rolf

Forward Declarations

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