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program simple;
{$mode objfpc}{$H+}
uses
{$IFDEF UNIX}{$IFDEF UseCThreads}
cthreads,
{$ENDIF}{$ENDIF}
Classes,
zorba,
ctypes;
{$IFDEF WINDOWS}{$R simple.rc}{$ENDIF}
procedure stream_write(stream: XQC_OutputStream; const buf: pchar; length: cuint); cdecl;
var
S: String;
begin
SetLength(S, length);
Move(buf^, S[1], length);
WriteLn(S);
end;
procedure stream_free(stream: XQC_OutputStream); cdecl;
begin
end;
const
streamdef: XQC_OutputStream_s = (
write:@stream_write;
free:@stream_free;
data:nil
);
var
stream: XQC_OutputStream = @streamdef;
(**
* A simple C API example
* Compile a query and print the result. No error checking is done.
*)
function example_1(impl: XQC_Implementation): boolean;
var
lXQuery: XQC_Query;
begin
// compile the query
impl^.prepare(impl, '(1+2, 3, 4)', nil, nil, lXQuery);
// execute it and print the result on standard out
lXQuery^.serialize_stream(lXQuery, nil, stream);
// release the query
lXQuery^.free(lXQuery);
Result := True;
end;
(**
* A simple C API example
* Compile a query, iterate over the item sequence, and print the string value for each item.
* No error checking is done.
*)
function example_2(impl: XQC_Implementation): boolean;
var
lXQuery : XQC_Query;
lItem : XQC_Item;
lResult : XQC_Sequence;
lStringValue : pchar;
begin
impl^.create_item(impl, lItem);
// compile the query and get the result as a sequence
impl^.prepare(impl, 'for $i in 1 to 10 return $i', nil, nil, lXQuery);
lXQuery^.sequence(lXQuery, lResult);
while lResult^.next(lResult, lItem) = XQ_NO_ERROR do
begin
lItem^.string_value(lItem, &lStringValue);
write(lStringValue, ' ');
end;
writeln;
// release all aquired resources
lItem^.free(lItem);
lResult^.free(lResult);
lXQuery^.free(lXQuery);
Result := True;
end;
var
impl: XQC_Implementation;
store: Pointer;
begin
store := create_simple_store();
if zorba_implementation(impl, store) <> XQ_NO_ERROR then
Exit;
writeln('executing PASCAL example 1');
if not example_1(impl) then
Exit;
writeln;
writeln('executing PASCAL example 2');
if not example_2(impl) then
Exit;
writeln;
impl^.free(impl);
shutdown_simple_store(store);
end.
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