procedure       _Copy{ s : ShortString; index, count : Integer ) : ShortString};
asm
{     ->EAX     Source string                   }
{       EDX     index                           }
{       ECX     count                           }
{       [ESP+4] Pointer to result string        }

        PUSH    ESI
        PUSH    EDI

        MOV     ESI,EAX
        MOV     EDI,[ESP+8+4]

        XOR     EAX,EAX
        OR      AL,[ESI]
        JZ      @@srcEmpty

{       limit index to satisfy 1 <= index <= Length(src) }

        TEST    EDX,EDX
        JLE     @@smallInx
        CMP     EDX,EAX
        JG      @@bigInx
@@cont1:

{       limit count to satisfy 0 <= count <= Length(src) - index + 1    }

        SUB     EAX,EDX { calculate Length(src) - index + 1     }
        INC     EAX
        TEST    ECX,ECX
        JL      @@smallCount
        CMP     ECX,EAX
        JG      @@bigCount
@@cont2:

        ADD     ESI,EDX

        MOV     [EDI],CL
        INC     EDI
        REP     MOVSB
        JMP     @@exit

@@smallInx:
        MOV     EDX,1
        JMP     @@cont1
@@bigInx:
{       MOV     EDX,EAX
        JMP     @@cont1 }
@@smallCount:
        XOR     ECX,ECX
        JMP     @@cont2
@@bigCount:
        MOV     ECX,EAX
        JMP     @@cont2
@@srcEmpty:
        MOV     [EDI],AL
@@exit:
        POP     EDI
        POP     ESI
    RET 4
end;