understanding string manipulations

NamNori · 2014-01-09 22:27

Hello:

In attempting to do some string manipulation, I quickly figured out that I'm not sure of what I'm doing.

I had wanted to concatenate 2 strings into a single variable, and found other posts on the forum showing how to do so with some ByteMove statements. But it's not working for me; obviously I went south somewhere here... I was attempting to simply concatenate src1 with src2 into dest. My first ByteMove statement works, but the second one doesn't do anything. And by putting the addresses out to the serial terminal, I see that when it's all done, both the dest and the src1 variables have the same address? Doesn't seem right to me. I've played with adding/removing the "@" to/from the variables within ByteMove, and it only seems to work with @ in place like it is below.

I'm probably not understanding some fundamental aspect here, and am hoping somebody can clear up my misunderstanding.

thanks!
-marc

CON
  _clkmode  = xtal1 + pll16x           
  _xinfreq  = 5_000_000                

OBJ
  PST           : "Parallax Serial Terminal"

VAR
  byte dest[10]
  byte src1
  byte src2

PUB Main

  PST.Start(115200)                                  
  PST.Home
  PST.Clear
  
  Src1 := String("abc")
  Src2 := String("def")

  PST.Str(String("Src1: "))
  PST.Str(src1)
  PST.NewLine
  PST.Str(String("Src2: "))
  PST.Str(src2)
  PST.NewLine

  PST.Hex(src1, 2)
  PST.NewLine
  PST.Hex(src2, 2)
  PST.NewLine
  
  ByteMove(@dest, @src1, StrSize(src1))
  ByteMove(@dest + StrSize(src1), @src2, StrSize(src2) + 1)
  
  PST.Str(String("Dest: "))
  PST.Str(dest)
  PST.NewLine
  PST.Hex(dest, 2)
  PST.NewLine
  PST.Hex(src1, 2)

kuroneko · 2014-01-09 23:21

Declare src1 and src2 at least as word variables. In the bytemoves get rid of the @ for the source (src? is already an address) i.e.:

ByteMove(@dest, src1, StrSize(src1))
  ByteMove(@dest + StrSize(src1), src2, StrSize(src2) + 1)

Followed by:

PST.Str(String("Dest: "))
  PST.Str([COLOR="#FF0000"]@[/COLOR]dest)
  PST.NewLine
  PST.Hex([COLOR="#FF0000"]@[/COLOR]dest, 4)
  PST.NewLine
  PST.Hex(src1, 4)

NamNori · 2014-01-11 22:15

Yep, that did the trick. I clearly have a lot to learn! Thanks!

StefanL38 · 2014-01-12 13:10

Hi,

a longer time ago I made a oo-sheet explaining stringmanipulation

see attachment

best regards
Stefan

cavelamb · 2014-01-12 15:45

StefanL38 wrote: »

Hi,

a longer time ago I made a oo-sheet explaining stringmanipulation

see attachment

best regards
Stefan

Hi Stephan,

Can't open the file.
My apologies for being a pain about this - but could you post that in a more accessible form?
Text maybe?

StefanL38 · 2014-01-12 20:43

https://www.google.de/search?as_q=fileextension+ods&as_epq=&as_oq=&as_eq=&as_nlo=&as_nhi=&lr=&cr=&as_qdr=all&as_sitesearch=&as_occt=any&safe=images&as_filetype=&as_rights=

kuroneko · 2014-01-12 21:31

@StefanL38: Did you ever verify the code examples you show in the document?

StefanL38 · 2014-01-12 21:35

kuroneko wrote: »

@StefanL38: Did you ever verify the code examples you show in the document?

No. The main purpose is to show how strings are handled and what pointers are. If you're asking this way I guess you found bugs.
Please report them
best regards
Stefan

understanding string manipulations

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