$extendedSyntax

The global compiler directive {$extendedSyntax on} turns on additional syntax. The FPC has this by default on. The short notation is {$X+}/{$X‑}.

affected syntax

• Functions can be called as if they were procedures. The function result is discarded. This is potentially harmful if, for example, the function allocated new memory space and returned a pointer to it.
• Integer arithmetic operations are allowed on pointers. The directive {$pointerMath} had to be on for that during the respective pointer type’s definition.
• Pointers become ordered and can be compared using <,>, <= and >=. Typed pointers have to correspond to each other. The = and <> comparisons work regardless of the {$extendedSyntax} state.

comparative remarks

• Standard Pascal does not define any of those “extensions”.
• {$X+} and {$X‑} in GPC enables and disables full Extended Pascal compliance.

see also

• Pascal for C users