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reply Qian Xu <quian.xu stud.tu-ilmenau.de> writes:
Hi All,

I am new to D community. I have some problems with TimeOfDay struct.

I have defined a class:
========================================================
   class Test
   {
     TimeOfDay* getTime() {
       return a_valid_timeofday_pointer;
     }
     void setTime(TimeOfDay* value) {
       setValueAsTime(*value);
     }
     void setValueAsTime(TimeOfDay value) {
       Cout(TimeToChar(value)).newline;
     }
     /* the rest implementation of this class ... */
   }
========================================================

I try to test if setTime() works properly.

If I call
   Cout(TimeToChar(*TestObj.getTime())).newline;
It works. The console will show "10:00:00" for example.

If I call
   TestObj.setTime(TestObj.getTime());
It does not work. The console will show "33140305:48698544:485947594" 
for example.

If I change the setTime() function to
   void setTime(TimeOfDay* value) {
     Cout(TimeToChar(*value)).newline;
   }
or
   void setTime(TimeOfDay* value) {
     TimeOfDay copy = *value;
     setValueAsTime(copy);
   }
It works.

What's wrong with my code? (BTW: I do not want to change TimeOfDay* to 
TimeOfDay, otherwise null cannot be passed in.)

Thanks in advance.
-- 
Xu, Qian (stanleyxu)
  http://stanleyxu2005.blogspot.com
Dec 14 2008
parent reply BCS <ao pathlink.com> writes:
Reply to Qian,


 Hi All,
 
 I am new to D community. I have some problems with TimeOfDay struct.
 
 I have defined a class:
 ========================================================
 class Test
 {
 TimeOfDay* getTime() {
 return a_valid_timeofday_pointer;
 }


Could you expand on this function? The rest looks good but if this function 
is returning a pointer to something that then goes out of scope (a local 
var for instance) than that would be the bug.


 void setTime(TimeOfDay* value) {
 setValueAsTime(*value);
 }
 void setValueAsTime(TimeOfDay value) {
 Cout(TimeToChar(value)).newline;
 }
 /* the rest implementation of this class ... */
 }
 ========================================================
 I try to test if setTime() works properly.
 
 If I call
 Cout(TimeToChar(*TestObj.getTime())).newline;
 It works. The console will show "10:00:00" for example.
 If I call
 TestObj.setTime(TestObj.getTime());
 It does not work. The console will show "33140305:48698544:485947594"
 for example.
 
 If I change the setTime() function to
 void setTime(TimeOfDay* value) {
 Cout(TimeToChar(*value)).newline;
 }
 or
 void setTime(TimeOfDay* value) {
 TimeOfDay copy = *value;
 setValueAsTime(copy);
 }
 It works.
 What's wrong with my code? (BTW: I do not want to change TimeOfDay* to
 TimeOfDay, otherwise null cannot be passed in.)
 
 Thanks in advance.
Dec 14 2008
next sibling parent Qian Xu <quian.xu stud.tu-ilmenau.de> writes:
BCS wrote:

 Reply to Qian,
 

 Hi All,

 I am new to D community. I have some problems with TimeOfDay struct.

 I have defined a class:
 ========================================================
 class Test
 {
 TimeOfDay* getTime() {
 return a_valid_timeofday_pointer;
 }


 
 Could you expand on this function? The rest looks good but if this 
 function is returning a pointer to something that then goes out of scope 
 (a local var for instance) than that would be the bug.
 


Thanks BCS, I am not able to get my own code right now. I will post it 
tomorrow.


-- 
Xu, Qian (stanleyxu)
  http://stanleyxu2005.blogspot.com
Dec 14 2008
prev sibling parent Qian Xu <quian.xu stud.tu-ilmenau.de> writes:
BCS wrote:

 Reply to Qian,
 

 Hi All,

 I am new to D community. I have some problems with TimeOfDay struct.

 I have defined a class:
 ========================================================
 class Test
 {
 TimeOfDay* getTime() {
 return a_valid_timeofday_pointer;
 }


 
 Could you expand on this function? The rest looks good but if this 
 function is returning a pointer to something that then goes out of scope 
 (a local var for instance) than that would be the bug.
 


Hi, it was my fault.

My wrong code was:
========================================
   public TimeOfDay* getTime() {
     char[] timestring = "10:00:00"; // for test
     FullDate fd;
     parseTime(timestring, fd);
     return *fd.val.time();
   }
========================================

Today I have changed it to:
========================================

   public TimeOfDay* getTime() {
     char[] timestring = "10:00:00"; // for test
     FullDate fd;
     parseTime(timestring, fd);
     TimeOfDay* ret = new TimdOfDay();
     *ret = fd.val.time();
     return ret;
   }
========================================

Now it works properly.



-- 
Xu, Qian (stanleyxu)
  http://stanleyxu2005.blogspot.com
Dec 15 2008