In {$MODE TP} refuses to compile 1+PChar, but compiling PChar+1

[Avinash]

Code: Pascal  [Select][+][-]

1. {$MODE TP}
2. var P: PChar;
3. begin
4.   P := 1 + P;
5. end.

Error: Operation "+" not supported for types "ShortInt" and "PChar"

Code: Pascal  [Select][+][-]

1. {$MODE TP}
2. var P: PChar;
3. begin
4.   P := P + 1;
5. end.

OK

[AlexTP]

Order of operands matters.

[Avinash]

Very well noticed. But I meant that since the order does not matter for MODE FPC, OBJFPC and Turbo Pascal compiler itself (with that the {$MODE TP} mode should be compatible), most likely something wrong here.

[marcov]

Is this syntax supported by TP?

[Avinash]

With the "Extended syntax" {$X+} (is on by default) TPC compiles both cases, with {$X-} none.

Just like FPC does (Free Pascal Programmer’s Guide):

1.3.40 $X or $EXTENDEDSYNTAX : Extended syntax
Extended syntax allows you to drop the result of a function and perform pointer arithmetic. This means that you can use a function call as if it were a procedure. By default this feature is on.