# Array of const
**URL:** https://talk.remobjects.com/t/array-of-const/1627
**Category:** Pascal Script
**Created:** [February 1, 2013, 6:53pm UTC](https://talk.remobjects.com/t/array-of-const/1627 "2013-02-01T18:53:07Z")
**Posts on this page:** 10
**Page:** 1
### Author:  [@nomorelogic](https://talk.remobjects.com/u/nomorelogic)
#### Post date: [February 1, 2013, 6:53pm UTC](https://talk.remobjects.com/t/array-of-const/1627/1 "2013-02-01T18:53:07Z")
hi guys
first of all congratulation for your work, very very well done!
I’m a fpc programmer and I’m experimenting with your interpreter, so, sorry if I ask trivial things.
With free pascal I wrote a function like:
procedure Out\_WriteFmt(Data: string; const Args : array of const);
begin
ScriptOutput.Text:= ScriptOutput.Text + Format(Data, Args);
end;
The purpose is to provide the potential of the Format function to my script.
I can use it properly (both compilation and runtime), but at the end of runtime I get an Access Violation.
I guess it depends on the parameter: const Args: array of const.
I don’t think that it is not supported (function produces output that I expect) but I cannot understand the access violation.
Thanks in advance
nomorelogic
---
### Author:  [@vovanl](https://talk.remobjects.com/u/vovanl)
#### Post date: [February 5, 2013, 2:10pm UTC](https://talk.remobjects.com/t/array-of-const/1627/2 "2013-02-05T14:10:35Z")
Hello,
Can you send us your small testcase? We will retest it.
---
### Author:  [@nomorelogic](https://talk.remobjects.com/u/nomorelogic)
#### Post date: [February 5, 2013, 7:20pm UTC](https://talk.remobjects.com/t/array-of-const/1627/3 "2013-02-05T19:20:54Z")
sure
in attached file both fpc binary and pascal script
to use run from shell as:
./lpitr -s script03.pas
As you can see in script03.pas I wrote 2 procedures: Out\_Write and Out\_WriteFmt.
The first one runs correctly, the last give a error.
Note also that “Now” (from dateutils) returns an invalid date.
Thanks
nomorelogic
PS:
linux 64 bit
lazarus 1.06
fpc 2.6.0
---
### Author:  [@vovanl](https://talk.remobjects.com/u/vovanl)
#### Post date: [February 10, 2013, 6:49pm UTC](https://talk.remobjects.com/t/array-of-const/1627/4 "2013-02-10T18:49:42Z")
Hello,
Thanks, issues were logged as #32 and #33.
We will send you a workaround after fixing.
---
### Author:  [@nomorelogic](https://talk.remobjects.com/u/nomorelogic)
#### Post date: [February 11, 2013, 2:18pm UTC](https://talk.remobjects.com/t/array-of-const/1627/5 "2013-02-11T14:18:03Z")
thanks
---
### Author:  [@spriya](https://talk.remobjects.com/u/spriya)
#### Post date: [December 20, 2022, 2:32pm UTC](https://talk.remobjects.com/t/array-of-const/1627/6 "2022-12-20T14:32:34Z")
Hi,
facing the same problem with array of const when using in Format(Data, Args);
Am not getting the access violation, but getting weird characters in place of original arguments.
waiting for solution.
Thanks in advance
---
### Author:  [@EvgenyK](https://talk.remobjects.com/u/EvgenyK)
#### Post date: [January 4, 2023, 12:54pm UTC](https://talk.remobjects.com/t/array-of-const/1627/7 "2023-01-04T12:54:58Z")
Hi,
looks like delphi RTTI can’t work with `array of const` parameters
try this testcase:
```auto
program Project13;
{$APPTYPE CONSOLE}
{$R *.res}
uses
System.SysUtils, System.Rtti, system.TypInfo;
begin
var res := Invoke(@Format,
['this is string - %s, %d',
TValue.FromArray(TypeInfo(TArray),
ArrayOfConstToTValueArray(['string',123]))],
ccReg,
TypeInfo(string),
true);
writeln(res.AsString);
end.
```
---
### Author:  [@holly.lee](https://talk.remobjects.com/u/holly.lee)
#### Post date: [May 10, 2024, 4:28pm UTC](https://talk.remobjects.com/t/array-of-const/1627/8 "2024-05-10T16:28:01Z")
After some hours digging into fewer documentation and writing some test codes. I found the correct way to do the Rtti invoke call with array of const parameters
```auto
procedure F3(a: array of const);
var
i: Integer;
begin
Writeln('F3: Length of a is ' + IntToStr(Length(a)));
for i := Low(a) to High(a) do begin
if a[i].VType = vtUnicodeString then
Writeln(IntToStr(i) + ': UnicodeString ' + UnicodeString(a[i].VUnicodeString))
else if a[i].VType = vtInteger then
Writeln(IntToStr(i) + ': Integer ' + IntToStr(a[i].VInteger));
// and other types...
end;
end;
procedure CallF3ThroughRtti(a: array of const);
var
Args: TArray;
begin
SetLength(Args, 2);
Args[0] := TValue.From(@a[0]);
Args[1] := TValue.From(High(a));
Invoke(@F3, Args, ccReg, nil, True);
end;
```
Hope this can help others entering into this topic later.
---
### Author:  [@EvgenyK](https://talk.remobjects.com/u/EvgenyK)
#### Post date: [May 13, 2024, 8:42am UTC](https://talk.remobjects.com/t/array-of-const/1627/9 "2024-05-13T08:42:38Z")
Hi,
yes, this works:
```auto
program Project26;
{$APPTYPE CONSOLE}
{$R *.res}
uses
System.SysUtils, System.Rtti, system.TypInfo;
var
res: TValue;
args: TArray;
a: TArray;
begin
a := TValueArrayToArrayOfConst(['string', 123]);
res := Invoke(@Format,
[ 'this is string - %s, %d',
@a[0],
High(a)],
ccReg,
TypeInfo(string),
true);
writeln(res.AsString);
end.
```
---
### Author:  [@EvgenyK](https://talk.remobjects.com/u/EvgenyK)
#### Post date: [May 14, 2024, 7:44am UTC](https://talk.remobjects.com/t/array-of-const/1627/10 "2024-05-14T07:44:20Z")
Hi,
I’ve fixed [Array of const broken? · Issue #267 · remobjects/pascalscript · GitHub](https://github.com/remobjects/pascalscript/issues/267)