Simple While loop problem

vmail · May 2017

Hi have a simple while loop and I don't know what's wrong, I want the contents of the Line variable spilt by commas to be placed in a structure.

Line = ",105,103,125,117,102,116,126,113,112,119,108,109,110,118"
WHILE(LENGTH_STRING(Line) > 2){
    Sources.ButtonNo[count] = ATOI(REMOVE_STRING(Line, ',', 1))
    count=count+1
}

The loop never stops, If I clear the contents of the Line variable in debug then the loop stops and the structure is populated.

ericmedley · May 2017

My guess is your specification that the length of the var after removing the "," is greater than 2 chars. Debug can fool you when you're viewing the value of a char variable. You may see only one or even zero chars in the value window but in fact there are a couple chars left like $A,$D or whatnot. (Chars that are non-ascii and don't showup but are there just the same) You can doulbe check this by switching the view from ASCII to HEX. Or even easier yet - the length of the string is shown as well.

Another thing to bear in mind is that when you hit the last number, there is no longer a comma to remove. So "Line" will be stuck at 3 chars long. You might want to put the whole evaluation inside an if(find_string(Line,',',1)) statement. That way when you're on the last number you'll know because the find_string:comma will fail. you could do something like this:

if(find_stirng(Line,',',1){
  Sources.ButtonNo[count] = ATOI(REMOVE_STRING(Line, ',', 1))
  count=count+1
} // if find_string
else if(length_string(Line))){ // last char
  Sources.ButtonNo[count] = ATOI(Line);
  Line='' /// clear out last number - making Line length zero and killing the loop
  }// else

vmail · May 2017

Thank you.

vmail · May 2017

It's like REMOVE_STRING (on line 2) is not updated til you are out of the while loop. EG, On the third line I'm looking for "Obs Cabin2" which does not exist in the file, the main while loop (line 1) keeps going.

WHILE(LENGTH_STRING(SOURCESDATA > 0)){
    Line = REMOVE_STRING(SOURCESDATA, CRLF, 1)
    If(FIND_STRING(Line, 'Obs Cabin2' , 1)){
        count=1
        WHILE(LENGTH_STRING(Line) > 0){
            If(FIND_STRING(Line, ',' , 1)){
                Sources.Enable[count] = ATOI(REMOVE_STRING(Line, ',', 1))
                count=count+1
            }Else{ // last char
                Sources.Enable[count] = ATOI(Line);
                Line='' /// clear out last number - making Line length zero and killing the loop
            }
        }
        Break
    }
}

Joe Hebert · May 2017

vmail wrote: »
It's like REMOVE_STRING (on line 2) is not updated til you are out of the while loop. EG, On the third line I'm looking for "Obs Cabin2" which does not exist in the file, the main while loop (line 1) keeps going.
WHILE(LENGTH_STRING(SOURCESDATA > 0)){
Line = REMOVE_STRING(SOURCESDATA, CRLF, 1)
If(FIND_STRING(Line, 'Obs Cabin2' , 1)){
count=1
WHILE(LENGTH_STRING(Line) > 0){
If(FIND_STRING(Line, ',' , 1)){
Sources.Enable[count] = ATOI(REMOVE_STRING(Line, ',', 1))
count=count+1
}Else{ // last char
Sources.Enable[count] = ATOI(Line);
Line='' /// clear out last number - making Line length zero and killing the loop
}
}
Break
}
}

The function REMOVE_STRING() is not the problem here. Your *logic* is the culprit.

Line 1:

WHILE(LENGTH_STRING(SOURCESDATA > 0)){

evaluates to TRUE if anything is in SOURCEDATA

Line 3:

If(FIND_STRING(Line, 'Obs Cabin2' , 1)){

evaluates to TRUE if Obs Cabin2 exists in the Line variable.

Why should a FALSE for Line 3 automatically assume Line 1 is FALSE? They have nothing to do with each other.

vining · May 2017

If your delimiter is always CRLF I would use while(find_string(source,crlf,1)) line = remove the same. Likewise in your next while if that delimeter is , I would do the same while find string, remove string type of approach. You must make sure your loops exit so test a while for one thing and then doing something else with out an escape hatch is dangerous.

vmail · May 2017

Joe Hebert wrote: »
The function REMOVE_STRING() is not the problem here. Your *logic* is the culprit.

Line 1:
WHILE(LENGTH_STRING(SOURCESDATA > 0)){
evaluates to TRUE if anything is in SOURCEDATA

Line 3:
If(FIND_STRING(Line, 'Obs Cabin2' , 1)){
evaluates to TRUE if Obs Cabin2 exists in the Line variable.

Why should a FALSE for Line 3 automatically assume Line 1 is FALSE? They have nothing to do with each other.

Hi, Line 2 should be removing one line at a time from SOURCESDATA, when all lines have gone then line 1 should return FALSE.

vmail · May 2017

vining wrote: »

If your delimiter is always CRLF I would use while(find_string(source,crlf,1)) line = remove the same. Likewise in your next while if that delimeter is , I would do the same while find string, remove string type of approach. You must make sure your loops exit so test a while for one thing and then doing something else with out an escape hatch is dangerous.

Thanks....

Simple While loop problem

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