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program sample1;
uses
uPSCompiler, uPSRuntime;
function ScriptOnUses(Sender: TPSPascalCompiler; const Name: AnsiString): Boolean;
{ the OnUses callback function is called for each "uses" in the script.
It's always called with the parameter 'SYSTEM' at the top of the script.
For example: uses ii1, ii2;
This will call this function 3 times. First with 'SYSTEM' then 'II1' and then 'II2'.
}
begin
if Name = 'SYSTEM' then
begin
Result := True;
end else
Result := False;
end;
procedure ExecuteScript(const Script: string);
var
Compiler: TPSPascalCompiler;
{ TPSPascalCompiler is the compiler part of the scriptengine. This will
translate a Pascal script into a compiled form the executer understands. }
Exec: TPSExec;
{ TPSExec is the executer part of the scriptengine. It uses the output of
the compiler to run a script. }
Data: AnsiString;
begin
Compiler := TPSPascalCompiler.Create; // create an instance of the compiler.
Compiler.OnUses := ScriptOnUses; // assign the OnUses event.
if not Compiler.Compile(Script) then // Compile the Pascal script into bytecode.
begin
Compiler.Free;
// You could raise an exception here.
Exit;
end;
Compiler.GetOutput(Data); // Save the output of the compiler in the string Data.
Compiler.Free; // After compiling the script, there is no need for the compiler anymore.
Exec := TPSExec.Create; // Create an instance of the executer.
if not Exec.LoadData(Data) then // Load the data from the Data string.
begin
{ For some reason the script could not be loaded. This is usually the case when a
library that has been used at compile time isn't registered at runtime. }
Exec.Free;
// You could raise an exception here.
Exit;
end;
Exec.RunScript; // Run the script.
Exec.Free; // Free the executer.
end;
const
Script = 'var s: string; begin s := ''Test''; S := s + ''ing;''; end.';
begin
ExecuteScript(Script);
end.
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