Functions Example

[kryton9]

Code: OxygenBasic

1. function half( double amount ) as double
2.         return  amount / 2 'you can use return as shown here, the c way
3. end function
4.  
5. function qrtr( double amount ) as double
6.         function = amount / 4 'you can return this way, the traditional way
7. end function
8.  
9. 'to use functions that are defined below the program code
10. 'you need to declare it before the main program code
11. 'as shown with this next function
12. declare function tenth( double amount ) as double
13.  
14. 'Main Program
15. dim debt as double = 14432360075155.42
16.  
17. print "The U.S. debt as of 6/16/2011  8:45 A.M. = " debt
18. print "half of that is still so huge: " str( half( debt ) )
19. print "quarter is still an incredible amount: " str( qrtr( debt ) )
20. print "a king could wish for so much: " str( tenth( debt ) )
21. 'End of Main Program Code
22.  
23. 'now you can define the declared function
24. function tenth(double amount) as double
25.         return ( amount / 10 ) 'in c, it is recommended to return within ()
26. end function
27.  

[Charles Pegge]

Nice one Kent,

This is a variation with inner functions and a few other tricks!

I typedef'ed double so that "double half" and "double quarter" are avoided

Code: OxygenBasic

1.  
2. '===============
3. 'INNER FUNCTIONS
4. '===============
5.  
6. function DebtHorror(double debt,string datetime ) as string
7.  
8.   typedef double vt
9.   '
10.  vt half(vt amount)=amount*.5
11.   vt quarter(vt amount)=amount*.25
12.   vt tenth(vt amount)=amount*.1
13.   '
14.  string cr=chr(13)+chr(10)
15.   '
16.  return _
17.   '
18.  "The U.S. debt as of " datetime " = " debt cr+
19.   "half of that is still so huge: " half( debt )  cr+
20.   "quarter is still an incredible amount: " quarter( debt ) cr+
21.   "a king could wish for so much: " tenth( debt )
22.  
23. end function
24.  
25. print DebtHorror 14432360075155.42, "6/16/2011  8:45 A.M."
26.  
27.  

Charles

[kryton9]

Just curious to see if we needed the typedef and also to see if the return could be enclosed in ( ) over multiple lines, happy to say yes to both.

Code: OxygenBasic

1. '===============  
2. 'INNER FUNCTIONS
3. '===============  
4.  
5. function DebtHorror(double debt,string datetime ) as string  
6.  
7.         double half( double amount ) = amount * .5  
8.         double quarter( double amount ) = amount * .25  
9.         double tenth( double amount ) = amount * .1  
10.  
11.         string cr = chr(13) + chr(10)  
12.  
13.         return (  "The U.S. debt as of " datetime " = " debt cr+  
14.                         "half of that is still so huge: " half( debt )  cr+  
15.                         "quarter is still an incredible amount: " quarter( debt ) cr+  
16.                         "a king could wish for so much: " tenth( debt )   )
17.    
18. end function  
19.  
20. print DebtHorror 14432360075155.42, "6/16/2011  8:45 A.M."
21.  

[Aurel]

When we talk about functions i just test one simple but very useful function
which return number of delimited fields in given string.

Code: OxygenBasic

1. 'function - count fields in string
2. DECLARE FUNCTION FieldCount(String s,String d) As Int
3.  
4. Function FieldCount(string source,string delimiter)
5.         Dim delpos,nexpos,count As Int
6.         'delimiter=chr$(92)
7.         count=1
8.         delpos=1
9.         nexpos=InStr(source,delimiter)
10.         While nexpos > 0
11.                 delpos=nexpos
12.                 nexpos=InStr(source,delimiter,delpos+1)
13.                 count=count+1
14.         Wend
15.         Return delpos-1
16. End Function
17.  
18. INT fields
19. STRING src,d$
20. d$=" "
21. src="This is a delimited string"
22.  
23. 'call function
24. fields=FieldCount(src,d$)
25.  
26. Print Str(fields)
27.  

[kryton9]

Aurel, you can edit your post and put your source code in blocks like this to get syntax highlighting.

Press the # icon in message toolbars. You will see (code)(/code), well you will see them in brackets []. I just used () so that you can see what I meant without it creating the blocks.
Paste your code between the 2 code blocks.

Now change, (code)  to (code=o2), again replace the () with []

[Charles Pegge]

Thanks Aurel.

This extends your idea by supporting quoted fields. Delimiters inside the quotes are not counted.

Code: OxygenBasic

1.   '---------------------------------------------
2.  function fieldcount(string s, string d) as sys
3.   '=============================================
4.  sys a,b,c,le,i
5.   '
6.  'EXCLUDE EMPTY STRINGS
7.  '
8.  le=len s
9.   if le=0 then return 0
10.   if d="" then return 1
11.   '
12.  b=asc d 'delimiter ascii code
13.  c=1     'at least 1 field
14.  i=0     'char index
15.  do
16.     i++
17.     if i>le then exit do
18.     a=asc s,i
19.     '
20.    'SKIP QUOTED TEXT " ' `
21.    '
22.    if a=34 or a=39 or a=96 then
23.       do
24.         i++
25.         if i>le then exit do
26.         if asc(s,i)=a then  exit do
27.       end do
28.     end if
29.     if a=b then c++
30.   end do
31.   return c
32.   end function
33.  
34.  
35.   INT fields
36.   STRING src,d$
37.   d$=" "
38.   src="This is a delimited string 'and this a quoted field'"
39.  
40.   'call function
41.  fields=FieldCount(src,d$)
42.  
43.   Print Str(fields)
44.  
45.  

Charles

[Aurel]

Uf i miss this Charles example with quoted text.
And this is the function which i try to add in my parser.

Charles is there a way to replace do/end do loop with while/wend or do/until
becuse i dont have do/end do in ebasic?

[Charles Pegge]

My fingers produce do loops automatically but while loops are slightly shorter anyway.

Code: OxygenBasic

1. '---------------------------------------------  
2.  function fieldcount(string s, string d) as sys  
3.   '=============================================  
4.  sys a,b,c,le,i  
5.   '  
6.  'EXCLUDE EMPTY STRINGS  
7.  '  
8.  le=len s  
9.   if le=0 then return 0  
10.   if d="" then return 1  
11.   '  
12.  b=asc d 'delimiter ascii code  
13.  c=1     'at least 1 field  
14.  i=0     'char index  
15.  while i<le
16.    i+=1
17.    a=asc s,i  
18.     '  
19.    'SKIP QUOTED TEXT " ' `  
20.    '  
21.    if a=34 or a=39 or a=96 then  
22.       while i<le  
23.         i+=1  
24.         if i>le then exit while  
25.         if asc(s,i)=a then  exit while  
26.       wend  
27.     end if  
28.     if a=b then c+=1  
29.   wend  
30.   return c  
31.   end function  
32.  
33.  
34.   INT fields  
35.   STRING src,d$  
36.   d$=" "  
37.   src="This is a delimited string 'and this a quoted field'"  
38.  
39.   'call function  
40.  fields=FieldCount(src,d$)  
41.  
42.   Print Str(fields)
43.  
44.  

Charles

[Aurel]

Thank you..

[Aurel]

Charles maby im on right track to string extractor.
So next code present current shape of extractor which i use .
My question is how i can extract arguments into string array using
number of arguments as size of array.This sounds ok for me,right?
I know that i can use normal For/next loop...
but what with qouted string ,i mean how detect in this for loop
qouted string as one argument and extract complet quoted string as one
argument even is coma character inside this quoted string?
As you see i use coma as delimiter....

Any idea if you have time for this....

this is modified code:

Code: OxygenBasic

1. '---------------------------------------------  
2.  function fieldcount(string s, string d) as sys  
3.   '=============================================  
4.  sys a,b,c,le,i  
5.   '  
6.  'EXCLUDE EMPTY STRINGS  
7.  '  
8.  le=len s  
9.   if le=0 then return 0  
10.   if d="" then return 1  
11.   '  
12.  b=asc d 'delimiter ascii code  
13.  c=1     'at least 1 field  
14.  i=0     'char index  
15.  while i<le
16.    i+=1
17.    a=asc s,i  
18.     '  
19.    'SKIP QUOTED TEXT " ' `  
20.    '  
21.    if a=34 or a=39  
22.       while i<le  
23.         i+=1  
24.         if i>le then exit while  
25.         if asc(s,i)=a then  exit while  
26.       wend  
27.     end if  
28.     if a=b then c+=1  
29.   wend  
30.   return c  
31.   end function  
32.  
33.  
34.   INT numArg  'number of Arguments
35.  STRING src,d$  
36.   d$=","  
37.   src="arg1,arg2,arg3,arg4,'and with coma, quoted field',arg6"  
38.  
39.   'call function  
40.  numArg=FieldCount(src,d$)  
41.  
42.   Print Str(numArg)
43.  
44. 'extract arguments ******************************************
45.  
46. INT EPos,SPos
47. STRING arg1,arg2
48. EPos=0
49. SPos=0
50. '==========================================================
51. 'first argument
52. IF numArg>0
53. SPos=1
54.  EPos = InStr(SPos,src, ",")-1
55. Print "EPos:"+str(EPos)
56.  If EPos <= 0 Then EPos = Len(src)
57.  arg1 = RTrim(LTrim(Mid(src, SPos, EPos - SPos + 1)))  
58. END IF
59.  
60. Print "ARG:"+arg1
61. '=============================================================
62. 'second argument
63. IF numArg>1
64.  SPos = EPos+2
65.  EPos = InStr(SPos,src, ",") - 1
66. Print "EPos:"+str(EPos)
67.  If EPos <= 0 Then EPos = Len(src)
68.  arg2 = RTrim(LTrim(Mid(src, SPos, EPos - SPos + 1)))  
69. END IF
70.  
71. Print "ARG:"+arg2

[Charles Pegge]

Will this do?
All the params exclude end spaces.

Code: OxygenBasic

1.  
2.   '==============
3.  'CAPTURE PARAMS
4.  '==============
5.  
6.  
7.   dim as string arg(64) 'params array
8.  
9.   '--------------------------------------------  
10.  function GetFields(string s, string d) as sys    
11.   '============================================
12.  '
13.  sys a,b,c,le,i
14.   sys bg,en 'beginning and end of param    
15.  '
16.  '    
17.  'EXCLUDE EMPTY STRINGS    
18.  '    
19.  le=len s    
20.   if le=0 then return 0    
21.   if d="" then return 0    
22.   '    
23.  b=asc d 'delimiter ascii code    
24.  i=0     'char index    
25.  while i<le  
26.     i+=1  
27.     a=asc s,i
28.     '
29.    'MARK START OF PARAM
30.    '
31.    if bg=0 then
32.       if a<>b then
33.         if a>32 then bg=i
34.       end if
35.     end if    
36.     '    
37.    'SKIP QUOTED TEXT " ' `    
38.    '    
39.    if a=34 or a=39 or a=96 then    
40.       while i<le    
41.         i+=1    
42.         if i>le then exit while    
43.         if asc(s,i)=a then  exit while    
44.       wend    
45.     end if
46.     '  
47.    'MARK END OF PARAM
48.    '
49.    if bg>0 then
50.       if a<>b then
51.         if a>32 then en=i
52.       end if
53.     end if
54.     '
55.    'DETECT DELIMITER
56.    '
57.    if (a=b)or(i>=le) then
58.       c+=1 'COUNT
59.      '
60.      'CAPTURE PARAM
61.      '
62.      if bg>0 then
63.         arg(c)=mid(s,bg,en-bg+1)
64.       else
65.         arg(c)=""
66.       end if
67.       bg=0 'CLEAR BEGIN MARKER
68.      en=0 'CLEAR END MARKER
69.    end if  
70.   wend    
71.   return c    
72.   end function    
73.  
74.   sys fields  
75.   string src,d$  
76.   d$=","  
77.   src="one, two,three, 'and, this, is, a, quoted, field'"  
78.  
79.   '
80.  fields=getFields(src,d$)  
81.  
82.   Print arg(3)
83.   Print arg(4)  
84.  

Charles

[Aurel]

WOW...
Excellent...Charles.
You are master of parsing that's for sure.
Thank you very much.

[kryton9]

What are you working on Aurel, got me curious?

[Aurel]

Hi Kent

For now i want write parser in Oxygen Basic and translate some things from ABasic scripting to
Oxygen program.I also will see if i can add some parsing methods into my include files.

[kryton9]

Thanks for filling me in. Parsing is fun, but it can get frustrating. Having routines will be nice. Good luck Aurel!