eg:
$string="This is my KiXtart string"

I would like
SUBSTR($string, 9) to return "my KiXtart string" without having to put SUBSTR($string, 9, len($string)-9)

cj

code:

---

$string="This is my KiXtart string"
SUBSTR($string, 9, 9999) ?

---

Will work fine.

------------------

Richard Howarth

------------------

Richard Howarth

[This message has been edited by rhowarth (edited 23 April 2001).]

Great idea!
I think that many of us makes a lot of unnessasary (timeconsuming ?) code when returning the 'rest' of a string.

Ofcourse we could use rhowarth's suggestion, but it would make the code more clear to read, if by default a 'missing' length parameter in SubStr() was equal to the 'rest' of the string.

Anyway it could make the size of the scripts smaller!

Erik

[This message has been edited by kholm (edited 23 April 2001).]

If a change to substr() was going to be made I'd strongly suggest keeping the three parameter format.

The bugs I take longest to track down are those involving overloaded operators and optional function arguments. And spelling mistakes

I suggest that the change should allow a negative value as the third parameter (some BASICs support this IIRC). For example...

code:

---

substr("NO BALL GAMES ALLOWED",4,-1) -> "BALL GAMES ALLOWED"
substr("ADOSFILE.TXT",5,-5) -> "FILE"

---

You keep the three parameters so function prototype checking will still catch you if you forget one, and you extend the usefulness of the function.

If you think the "9999" might be unclear in the current version, then:

code:

---

$EndOfString=9999
$string="This is my KiXtart string"
SUBSTR($string, 9, $EndOfString) ?

---

------------------

Richard Howarth

To keep things nice and simple perhaps the special case of zero for the length could be used to mean the rest of the string. It's certainly easy enough to type and read and would also provide backward compatability.

cj

To summarize:
substr(STRING,START,LENGTH)

Where:

code:

---

   START > 0 = Start position from start of STRING (1=1st character)
   START < 0 = Start position from end of STRING (-1=Last character, -2=penultimate character)
   LENGTH > 0 = Number of characters to substring
   LENGTH < 0 = Substring end position (-1=Last character in string)

---

Examples:

code:

---

   substr("A String",1,1) = "A"
   substr("A String",3,-1) = "String"
   substr("A String",3,-4) = "Str"
   substr("A String",-3,2) = "in"
   substr("A String",-4,-1) = "ring"
   substr("A String",-6,-4) = "Str"

---

------------------

Richard Howarth

Example, Function DoSomeThing($a,Optional $b, Optional $c):

This is legal(Strict Off, normal way of KiXtart):

$Res = DoSomeThing($a,$b,$c)
$Res = DoSomeThing($a,$b)
$Res = DoSomeThing($a,,$c)
$Res = DoSomeThing($a)

Whith a stricter syntax checking it should read like this, to be accepted(Strict On):

$Res = DoSomeThing($a,$b,$c)
$Res = DoSomeThing($a,$b,)
$Res = DoSomeThing($a,,$c)
$Res = DoSomeThing($a,,)

I just found cj's idea so good, that i have made this for my UDF liblary:

code:

---

Function SubString($String, $Start, Optional $Len)
   $SubString = ""
   If VarType($String) <> 8
      Return
   EndIf
   If VarType($Start) <> 3
      Return
   EndIf
   If VarType($Len) <> 3
      $Len = Len($String) - $Start + 1
   EndIf
   $SubString = SubStr($String, $Start, $Len)
EndFunction

---

rhowarth and Fuse, what do you think about this idea! (Of course Ruud would have to agree in making this option)

I think that it is correct to have the 'extra comma' just the way it is...

my 2c

cj

Sorry but I can't see the value of having strict checking as an option. I think it would most likely lead to sloppy coding habits which would no doubt be more difficult to debug, especially if coming back to code that hasn't been worked on for some time.

As for the two variations, the idea of having empty fields separated by commas is good because it is immediately clear that there is an optional field. Simply leaving fields out gives no clue that there may in fact be optional fields. Who can remember such details about all the functions we will collect over time, whether our own or somebody else's? Certainly not me.

It's always interesting to compare the way various languages implement such things. In the case of Visual Basic many otherwise poor ideas actually work quite well because there are on screen hints and reminders as you type. Other languages with similar features don't work so well because you are constantly having to check the help files and/or manuals. Kixtart would of course fall into this later group. Needles to say, things get even worse when we are talking about user written commands and functions, which do not even appear in the manual.

The sloppy code is allowed by default, allowing minimal codesize.

But when i made the suggestion i 'forgot' that KiXtart code is not compiled, the Strict On/Off would only be
usefull during compile time, or if someone makes a sort of pre-compiler.

So the Strict On/Off is not an issue to build into KiXtart itself, but a wish for a precompiler that will leave
a welldocumented code.

Function Add3($a,Optional $b,Optional $c)

; Strict code, always allowed
$Res = Add3($a,$b,)
$Res = Add3($a,,)

; Sloppy code, also allowed, this should not be allowed by a strict pre-compiler
$Res = Add3($a,$b)
$Res = Add3($a)

I see this forum as a sort of brainstorming, so your posts just brought op another idea to me. If the syntaxchecking is
not to deeply burried in the code, i would suggest that Ruud adds a PreKix.exe with the only purpose to check for
parameters (missing)

Erik

As for PreKiX.exe, MCA has written a number of scripts and programs that are great for checking for syntax errors, missing )'s etc... Goto the search page, select Scripts, enter 'kixtart - tool' in the search window and MCA in the user window. Then remove the 'kixtart - tool' and try that search in the other forums.

The latest versions of these great scripts is at http://home.wanadoo.nl/scripting.

cj

The discussion about correctness of parameter usage we like very
much.
At the moment we think about an extension of syntax checking of
this part. We will think about the usage of minimum required
parameters and the maximum of it.

CJ, we read with interest your way of finding tools + scripts
on our site.
To reach a wanted tool or script it is only necessary to
select the script button from the main screen from
the http://kixtart.org . All published software is placed
on one page.
We don't like it very much when users must check a lot of pages
to see the current state of the site.
Another element is the direct connection with the relevant
kixtart topic. Simply you must press the light icon of the
software item.
At least there is a History of Site and Summary of Site
page.
Greetings.

btw: according to CJ with add those page to the signature part.

------------------
Site:

• http://home.wanadoo.nl/scripting
  
• [url History]http://home.wanadoo.nl/scripting/history.htm]History of Site[/url]
  
• [url Summary]http://home.wanadoo.nl/scripting/summary.htm]Summary of Site[/url]
  

[This message has been edited by MCA (edited 15 May 2001).]

------------------
Site:

• http://home.wanadoo.nl/scripting
  
• http://home.wanadoo.nl/scripting/history.htm
  
• http://home.wanadoo.nl/scripting/summary.htm