Skip list "find" function

SystemAdmin - Tue Feb 26 03:31:19 EST 2013

Hi

Try
 

Skip skpSomeData = createString();
 
put(skpSomeData , "one", 1 "");

You cannot store an integer as an Skip-Data. You have to convert it into a string.

Best regards
Wolfgang

Tony_Goodman - Tue Feb 26 04:52:26 EST 2013

You CAN store integers in Skip data.
 

Skip s = createString
int i = 0
 
put(s, "one", 1)
put(s, "two", 2)
 
for i in s do
{
print (string key s) " " i "\n"
}
 
if (find(s, "one", i)) print i ""

Tony Goodman, www.smartdxl.com

SystemAdmin - Tue Feb 26 08:08:52 EST 2013
There is not strange behavior or reported issues with find. You do however have to implement find per the instructions in the help file.

SystemAdmin - Mon Mar 04 05:59:26 EST 2013

ok, I was probably too short before. I do use find in a few routines and it looks like it works just fine exept one place, which makes me crazy, because on the first glance I impement it the usual way.

Here is the code of main part and the call:

Skip SWCNames = createString()
...all other definitions ...
 
 
ReadSystags(Systg_ptr,SWCNames,SWCi,io4sys_tags)

Here ist the function:
I have a problem with Skip list "SWCNames", whatever I put there, the "find" finds only the first repetitive entry the rest is alway not found, and the "put" command then returns false, because the key is already in the skip list.
I was supposing maybe it copies the reference to the buffer and made temp string, but no change in behavoir: the find works only once correct, wenn it finds first existing occurence in the skip list. The rest of the time it returns true whatever I pass to it.

bool ReadSystags(Module &Md_ptr, Skip &SWCNames,int &SWCi,Stream &io4dst_log)
{
    if(null Md_ptr) {
                io4dst_log << "ERRO : [DOORSER0001] : module is null or is not opened\n"
                return false
        }
        Object o = null
        Buffer tmp = create
        string SWC = ""
        int cur_SWCi=SWCi
        bool find_status = false
        for o in Md_ptr do
        {
                SWC = o."SWC - out"
                string stmp = ""
                stmp = SWC
                find_status = find(SWCNames,stmp,cur_SWCi)
                if(!find_status) //if found, sets SWCi to the id of the SWCName
                {
                        //if not found add new SWC and its id
                        cur_SWCi++
                        if(put(SWCNames,SWC "",cur_SWCi)) 
                        {io4dst_log << "cannot add new entry to the list of SWC names\n" } else { io4dst_log << "Ok\n"}
                } 
..... some more stuff .....
 
        }
        delete tmp
        SWCi=cur_SWCi
        return true
}

Mathias Mamsch - Mon Mar 04 07:18:08 EST 2013

I can guarantee you that the skip lists, the very core of DXL work as expected.

You might have a logical error in there. Let me rephrase what I read from the code:
 

• Your ReadSystags fucntion reads the attribute value for the SWC - out attribute from the module
• for each value it finds, it will create an Integer ID (SWCi) and store it to the skip, the first time it finds it.
• When the function returns, it will return the last ID it has given (so not the next free one?)

If that is what you intended, the problem of your code seems to be, that you read the curSWI back from the skip:

...
find_status = find(SWCNames,SWC ,cur_SWCi)
...

The result of this, if you read the values "Hello", "World", "Hello", "New" is that

• "Hello" gets cur_cur_SWCi= 0
• "World" gets cur_cur_SWCi= 1
• "Hello" is found and resets cur_SWCi -> 0
• "New" gets cur_SWCi = 1 again ...

What also bothers me is that your log condition is inverted, it should have a ! (not) in front of it, because put will return true, when it puts the key in and false when the key already exists (which can never occur, since you have a the if find() { ... } block). So removing unnecessary redundany your code should look like this and be fine:

// You do not need to pass the skip as a reference, when you do not allocate it inside the function 
bool ReadSystags(Module &Md_ptr, Skip SWCNames,int &SWCi,Stream &io4dst_log)
{
    if(null Md_ptr) {
                io4dst_log << "ERRO : [DOORSER0001] : module is null or is not opened\n"
                return false
        }
 
        Object o = null
        Buffer tmp = create
        string SWC = ""
        int cur_SWCi=SWCi   // Good: You need to dereference the SWCi reference, before putting it in the skip
        bool find_status = false
        for o in Md_ptr do {  // Current Filter should be evaluated? 
                SWC = o."SWC - out"
                // Do not overwrite cur_SWCi here!?
                if( !find(SWCNames,SWC) ) {
                        cur_SWCi++
                        // put returns true if the item did not exist and could be added
                        if(! put(SWCNames, SWC, cur_SWCi) ) {
                            io4dst_log << "cannot add new entry to the list of SWC names\n" 
                        } else { 
                            io4dst_log << "Ok\n"
                        }
                } 
..... some more stuff .....
 
        }
        delete tmp
        SWCi = cur_SWCi
        return true
}

Hope that helps, regards, Mathias

Mathias Mamsch, IT-QBase GmbH, Consultant for Requirement Engineering and D00RS

SystemAdmin - Mon Mar 04 05:59:26 EST 2013

ok, I was probably too short before. I do use find in a few routines and it looks like it works just fine exept one place, which makes me crazy, because on the first glance I impement it the usual way.

Here is the code of main part and the call:

Skip SWCNames = createString()
...all other definitions ...
 
 
ReadSystags(Systg_ptr,SWCNames,SWCi,io4sys_tags)

Here ist the function:
I have a problem with Skip list "SWCNames", whatever I put there, the "find" finds only the first repetitive entry the rest is alway not found, and the "put" command then returns false, because the key is already in the skip list.
I was supposing maybe it copies the reference to the buffer and made temp string, but no change in behavoir: the find works only once correct, wenn it finds first existing occurence in the skip list. The rest of the time it returns true whatever I pass to it.

bool ReadSystags(Module &Md_ptr, Skip &SWCNames,int &SWCi,Stream &io4dst_log)
{
    if(null Md_ptr) {
                io4dst_log << "ERRO : [DOORSER0001] : module is null or is not opened\n"
                return false
        }
        Object o = null
        Buffer tmp = create
        string SWC = ""
        int cur_SWCi=SWCi
        bool find_status = false
        for o in Md_ptr do
        {
                SWC = o."SWC - out"
                string stmp = ""
                stmp = SWC
                find_status = find(SWCNames,stmp,cur_SWCi)
                if(!find_status) //if found, sets SWCi to the id of the SWCName
                {
                        //if not found add new SWC and its id
                        cur_SWCi++
                        if(put(SWCNames,SWC "",cur_SWCi)) 
                        {io4dst_log << "cannot add new entry to the list of SWC names\n" } else { io4dst_log << "Ok\n"}
                } 
..... some more stuff .....
 
        }
        delete tmp
        SWCi=cur_SWCi
        return true
}

Mathias Mamsch - Mon Mar 04 07:18:08 EST 2013

I can guarantee you that the skip lists, the very core of DXL work as expected.

You might have a logical error in there. Let me rephrase what I read from the code:
 

• Your ReadSystags fucntion reads the attribute value for the SWC - out attribute from the module
• for each value it finds, it will create an Integer ID (SWCi) and store it to the skip, the first time it finds it.
• When the function returns, it will return the last ID it has given (so not the next free one?)

If that is what you intended, the problem of your code seems to be, that you read the curSWI back from the skip:

...
find_status = find(SWCNames,SWC ,cur_SWCi)
...

The result of this, if you read the values "Hello", "World", "Hello", "New" is that

• "Hello" gets cur_cur_SWCi= 0
• "World" gets cur_cur_SWCi= 1
• "Hello" is found and resets cur_SWCi -> 0
• "New" gets cur_SWCi = 1 again ...

What also bothers me is that your log condition is inverted, it should have a ! (not) in front of it, because put will return true, when it puts the key in and false when the key already exists (which can never occur, since you have a the if find() { ... } block). So removing unnecessary redundany your code should look like this and be fine:

// You do not need to pass the skip as a reference, when you do not allocate it inside the function 
bool ReadSystags(Module &Md_ptr, Skip SWCNames,int &SWCi,Stream &io4dst_log)
{
    if(null Md_ptr) {
                io4dst_log << "ERRO : [DOORSER0001] : module is null or is not opened\n"
                return false
        }
 
        Object o = null
        Buffer tmp = create
        string SWC = ""
        int cur_SWCi=SWCi   // Good: You need to dereference the SWCi reference, before putting it in the skip
        bool find_status = false
        for o in Md_ptr do {  // Current Filter should be evaluated? 
                SWC = o."SWC - out"
                // Do not overwrite cur_SWCi here!?
                if( !find(SWCNames,SWC) ) {
                        cur_SWCi++
                        // put returns true if the item did not exist and could be added
                        if(! put(SWCNames, SWC, cur_SWCi) ) {
                            io4dst_log << "cannot add new entry to the list of SWC names\n" 
                        } else { 
                            io4dst_log << "Ok\n"
                        }
                } 
..... some more stuff .....
 
        }
        delete tmp
        SWCi = cur_SWCi
        return true
}

Hope that helps, regards, Mathias

Mathias Mamsch, IT-QBase GmbH, Consultant for Requirement Engineering and D00RS

Mathias Mamsch - Mon Mar 04 07:18:08 EST 2013

I can guarantee you that the skip lists, the very core of DXL work as expected.

You might have a logical error in there. Let me rephrase what I read from the code:
 

• Your ReadSystags fucntion reads the attribute value for the SWC - out attribute from the module
• for each value it finds, it will create an Integer ID (SWCi) and store it to the skip, the first time it finds it.
• When the function returns, it will return the last ID it has given (so not the next free one?)

If that is what you intended, the problem of your code seems to be, that you read the curSWI back from the skip:

...
find_status = find(SWCNames,SWC ,cur_SWCi)
...

The result of this, if you read the values "Hello", "World", "Hello", "New" is that

• "Hello" gets cur_cur_SWCi= 0
• "World" gets cur_cur_SWCi= 1
• "Hello" is found and resets cur_SWCi -> 0
• "New" gets cur_SWCi = 1 again ...

What also bothers me is that your log condition is inverted, it should have a ! (not) in front of it, because put will return true, when it puts the key in and false when the key already exists (which can never occur, since you have a the if find() { ... } block). So removing unnecessary redundany your code should look like this and be fine:

// You do not need to pass the skip as a reference, when you do not allocate it inside the function 
bool ReadSystags(Module &Md_ptr, Skip SWCNames,int &SWCi,Stream &io4dst_log)
{
    if(null Md_ptr) {
                io4dst_log << "ERRO : [DOORSER0001] : module is null or is not opened\n"
                return false
        }
 
        Object o = null
        Buffer tmp = create
        string SWC = ""
        int cur_SWCi=SWCi   // Good: You need to dereference the SWCi reference, before putting it in the skip
        bool find_status = false
        for o in Md_ptr do {  // Current Filter should be evaluated? 
                SWC = o."SWC - out"
                // Do not overwrite cur_SWCi here!?
                if( !find(SWCNames,SWC) ) {
                        cur_SWCi++
                        // put returns true if the item did not exist and could be added
                        if(! put(SWCNames, SWC, cur_SWCi) ) {
                            io4dst_log << "cannot add new entry to the list of SWC names\n" 
                        } else { 
                            io4dst_log << "Ok\n"
                        }
                } 
..... some more stuff .....
 
        }
        delete tmp
        SWCi = cur_SWCi
        return true
}

Hope that helps, regards, Mathias

Mathias Mamsch, IT-QBase GmbH, Consultant for Requirement Engineering and D00RS

SystemAdmin - Wed Mar 06 10:50:15 EST 2013

I have two questions regarding your comments, Mathias:

• passing the skip list as reference or not, what the difference? Can I extend it on other types? I was always curious with the string, thinking doors makes copy of it, if I pass it not as a reference, and this copy stay in memory until the program ends.
• what did you exactly mean with "Current filter should be evaluated?". Before the function call I make explicit

  filter off
  

  .

Mathias Mamsch - Wed Mar 06 16:27:31 EST 2013

If you read my post again, the problem with your code was described there:

You restored your cur_SWCi on the find call. Usually you wanted to increase the cur_SWCi for each new value that has been found. So if you got the values:
 

Hello  (cur_SWCi = 1)
World  (cur_SWCi = 2)
Hello  (cur_SWCi = 1) <<-- find resets the curSWCi to 1
DXL (cur_SWCi = 2) <<-- here the next new value will get 2 instead of 3 ..

Passing a Skip by reference is only necessary if you want to reallocate it, not if you want to use it. Example:

void get123 (Skip &sk) {
   Skip deref = sk   // dereference for null check 
   if (null deref) sk = create() 
   put (sk, 1,1, true)
   put (sk, 2,2, true)
   put (sk, 3,3, true)
}
 
Skip sk = null
 
// since sk is passed by reference you reallocating it, will change the sk variable
// this would not happen if sk was passed by value
get123(sk)  
 
int i; if (find(sk, 1, i)) print "Found: 1->" i "\n"

Regarding your filter question: There is a couple of view settings, than influence the for Object in Module loop. Sorting, Table Cells of, Filtering, Level, etc. All these settings can have strange effects for your DXL with objects not showing up in the loop or in the right order. Therefore I would always use:

for o in entire mod do {
   if (isDeleted o) continue
   // if (cell o || row o || table o) continue   // depending if you want to take into account table cells
   ...
}

This way you have no surprises. Regards, Mathias

Mathias Mamsch, IT-QBase GmbH, Consultant for Requirement Engineering and D00RS

SystemAdmin - Thu Mar 07 04:50:54 EST 2013
Hello Mathias,

thank you for the answers.

My comments, to your comments:

Actually, I use cur_SWCi the way I used it before - if the key is found in the skip list, cur_SWCi shall became the data of this key.
To track the IDs, there is one more variable. That is why I didn't exactly understand where the error was.
Passing Skip List as a reference: I am from the C/C++ world, so passing by reference means, I have acces to the data over the pointer. Passing by value means I copy the value to the subfunction. From your explanation I've got a feeling in dxl it works different.

Good Hint about filters - I will use it from now.

Tony_Goodman - Tue Feb 26 04:52:26 EST 2013

You CAN store integers in Skip data.
 

Skip s = createString
int i = 0
 
put(s, "one", 1)
put(s, "two", 2)
 
for i in s do
{
print (string key s) " " i "\n"
}
 
if (find(s, "one", i)) print i ""

Tony Goodman, www.smartdxl.com

Mark@V - Wed Jan 25 04:33:45 EST 2017

You CAN also use integers as a key in a skip list if you (postpend ??) them with ""

Skip s = createString
int i = 0
 
print (put(s, 0 "", 1)) "\n"
print (put(s, 1 "", 2)) "\n"
 
for i in s do
{
print (string key s) " " i "\n"
}
 
if (find(s, "one", i)) print i ""