StringBuilder for ThinBASIC @ GitHub

Hi all,

I am sure you are all familiar with the concept of StringBuilder - it is little helper which performs efficient string concatenations and often much more. I started working on such a component for ThinBASIC - the language has incredibly epic string handling, but didn't have any stringbuilder... till now!

The usage
... is very simple. You instantiate object, and then use its methods:

Code:

---

Uses "StringBuilder", "Console"     

Function TBMain()

  Dim stringBuffer As String
  Dim sb As StringBuilder
  sb = New StringBuilder()
 
  Long i
       
  Dim stopWatch As cTimer
  stopWatch = New cTimer()
 
  Print "Appending to classic string: "
  stopWatch.Start     
  For i = 1 To 20000
    stringBuffer += "Appending is fine!"
  Next           
  stopWatch.Stop
  PrintL stopWatch.ElapsedToString(%CTIMER_MILLISECONDS, "0") + " ms (Total " + Len(stringBuffer) + " characters)"
 
  Print "Appending to string builder: "
  stopWatch.Start     
  For i = 1 To 20000
    sb.Add("Appending is fine!")
  Next           
  stopWatch.Stop
  PrintL stopWatch.ElapsedToString(%CTIMER_MILLISECONDS, "0") + " ms (Total " + Len(sb.ToString()) + " characters)"
 
  PrintL
  PrintL "Press any key to quit..."
 
  WaitKey
 
End Function

---

What is it good for?
It is great for efficient string appending. Do you see the code above? Check the speed on your PC or see the screenshot...

The source code
I decided to make the code public, to make possible for others to commit their enhancements. Get the source @GitHub:
https://github.com/petrSchreiber/thi..._StringBuilder

The binaries
Please note StringBuilder is official part of thinBasic since 1.9.16.17! Yay!
You can still grab the latest release from GitHub as well.

Documentation
The documentation is provided at Wiki associated with the repository, please check here:
https://github.com/petrSchreiber/thi...ngBuilder/wiki

Petr

Hi Petr,

The timings are really impressive.

How would you comment on the following script and the associated snapshot, please?

Code:

---

Uses "StringBuilder", "Console"   
 
Function TBMain()
 
  Long i
       
  For i = 1 To 2000000
    SpawnStringBuilder
  Next           

  PrintL "Press any key to quit..."
 
  WaitKey
 
End Function

Sub SpawnStringBuilder()
  Dim sb As StringBuilder
  sb = New StringBuilder()

  sb.Capacity = 10000
  sb.Clear()
End Sub

---

Hi Mike,

well, that cries "memory leak" :) I am looking into it right now...


Petr

Thank you Mike,

I forgot the destruction must be handled on module side - now fixed.

Please redownload the DLL, and if curious, check the change in commit at git.

Early versions of the SDK freed the object, but when we discussed with Eros possiblity of non-COM based objects, it was changed to be freed by module creator.

From thinBasic programmer point of view, all objects are garbage collected - destuctor is called once they run out of scope.


Petr

Thanks a lot Petr,

In fact, git was the first place I poked my nose into. :) Now everything seems to be running just fine even without the sb.Clear() call.

Updated the module:

• .Add method can now take any number of parameters

Few tips on when to use this:

Code:

---

Uses "StringBuilder", "Console"     

Function TBMain()

  Dim stringBuffer As String
  Dim sb As StringBuilder
  sb = New StringBuilder()
 
  Long i
       
  Dim stopWatch As cTimer
  stopWatch = New cTimer()
 
  PrintL "Appending to classic string: "
  stopWatch.Start     
  For i = 1 To 20000
    stringBuffer += "Appending is fine! (" + i + ")"
  Next           
  stopWatch.Stop
  PrintL stopWatch.ElapsedToString(%CTIMER_MILLISECONDS, "0") + " ms (Total " + Len(stringBuffer) + " characters)"

  PrintL
  PrintL "Appending to classic string with StrFormat$: "
  stringBuffer = ""
  stopWatch.Start     
  For i = 1 To 20000
    stringBuffer += StrFormat$("Appending is fine! ({1})", i)
  Next           
  stopWatch.Stop
  PrintL stopWatch.ElapsedToString(%CTIMER_MILLISECONDS, "0") + " ms (Total " + Len(stringBuffer) + " characters)"

  PrintL
  PrintL "Appending to string builder with StrFormat$: "
  stopWatch.Start     
  For i = 1 To 20000
    sb.Add(StrFormat$("Appending is fine! ({1})", i))
  Next           
  stopWatch.Stop
  PrintL stopWatch.ElapsedToString(%CTIMER_MILLISECONDS, "0") + " ms (Total " + Len(sb.ToString()) + " characters)"
   
  PrintL
  PrintL "Appending to string builder with multiple parameters: "
  sb.Clear()
  stopWatch.Start     
  For i = 1 To 20000
    sb.Add("Appending is fine! (", i, ")")
  Next           
  stopWatch.Stop
  PrintL stopWatch.ElapsedToString(%CTIMER_MILLISECONDS, "0") + " ms (Total " + Len(sb.ToString()) + " characters)"
 
  PrintL
  printl "Press any key to quit..."
 
  WaitKey
 
End Function

---

Petr

Hi Petr
in the wiki you said :Place the thinBasic_stringBuilder.dll to Mod directory inside your thinBasic installation
but it seems the binary thinBasic_stringBuilder.dll is from 2015 while the source code is from 2016. even the old dll works but i want to be sure it is the correct file
the dll i found inside thinBasic_StringBuilder.zip.
thanks

Hi Primo,

thanks for letting me know. StringBuilder is now part of ThinBASIC default installation, you don't have to get it from GitHub, if you don't want to.
The binaries there are fresh!:
https://github.com/petrSchreiber/thi.../tag/1.9.16.17


Petr

I prepared new version of stringBuilder for thinBasic 1.9.16.18.
Users of older version can download the binaries here: https://github.com/petrSchreiber/thi.../tag/1.9.16.18

What is new? I added the DataPtr read-only property, which is handy for cases when you want to work with stringBuilders internal memory directly, for enhanced performance.
Full documentation here: https://github.com/petrSchreiber/thi...ngBuilder/wiki


Petr

Thanks Petr for the additional property DataPtr
i have tried it like this, but not sure if this is the correct usage:

Code:

---

Uses "StringBuilder", "Console"
Dim i As Long

Dim sb As New StringBuilder
 
sb.Add("Ciao world")
sb.Add("Ciao world")
 
Dim s As String * 4 At sb.DataPtr
 
PrintL s
Long pointer
pointer = sb.DataPtr
String st
For i=1 To 20
st = Peek$(pointer, i)
PrintL st
Next


WaitKey

---

Hi Primo,

perfectly valid, but this explicit length check is more safe:

Code:

---

Uses "StringBuilder", "Console"
 
Dim sb As New StringBuilder
 
sb.Add("Ciao world")
sb.Add("Ciao world")
 
Dim s As String * 4 At sb.DataPtr
 
PrintL s
printl
 
Long pointer
pointer = sb.DataPtr
String st
long i


For i=1 To sb.Length
  st = Peek$(pointer, i)
  PrintL st
Next
 
WaitKey

---

With this in mind, it is natural that you can reach the string inside like:

Code:

---

Uses "StringBuilder", "Console"
 
Dim sb As New StringBuilder
 
sb.Add("Ciao world")
sb.Add("Ciao world")
 
Dim s As String * sb.Length At sb.DataPtr
 
PrintL s
 
WaitKey

---

Petr

Hi Petr
you said in the announcement of TB 1.10.1 http://www.thinbasic.com/community/s...ll=1#post93686
that StringBuilder can be correctly initialized via string
what does that mean ?
you already have posted above how to initialize a StringBuilder

Code:

---

Dim sb As New StringBuilder
sb.Add("Ciao world")
sb.Add("Ciao world")
Dim s As String * sb.Length At sb.DataPtr
PrintL s

---

Hi primo,

I meant that you can do:

Code:

---

Dim sb As New StringBuilder("Ciao")

---

It will set initial text plus set internal capacity to double of initial text length (speed optimization for further additions).


Petr