(Recursive) nested loops and IFs?

[chromos]

Hi,
I'm writting solver for incomplete coordinates for multi caches (is there any geocacher out there?) which solves (brute force) inequalities, but their quantity and number of variables (and their names) is obtained from user via INPUT.

For six inequalities and four variables I have this static code:
(L1...coords via user input, something like {"5","0","3","5","(A+1)","(B)","(B-A-4)","0","1","5","2","4","(C-14)","(D-8)","(C-D+3)"}
L2...List of variable names,
L3, L4...Lists of variable boundaries,
L5...List of expressions
L6...valid variable values
Digitsum... digit sum of whole coordinates)

PHP Code:

SUBRFROMTO()
BEGIN
FOR Loop1 FROM L3(1) TO L4(1) DO
 PRINT(); 
 PRINT("



                        Completed: "+(Loop1*100/(L4(1)-L3(1)))+" %");
 FOR Loop2 FROM L3(2) TO L4(2) DO
  FOR Loop3 FROM L3(3) TO L4(3) DO
   FOR Loop4 FROM L3(4) TO L4(4) DO
    TempList:={};
    FOR Loop FROM 1 TO SIZE(L2) DO
     EXPR(L2(Loop)+":=Loop"+STRING(Loop));
     TempList(0):=EXPR(L2(Loop));
    END;
    Temp:=0;
    IF DigitSum>0 THEN
     FOR Loop FROM 1 TO SIZE(L5) DO
      Temp:=Temp+EXPR(L5(Loop));
     END;
    END;
    IF (NOT(DigitSum>0) OR Temp==DigitSum-SubDigitSum) THEN
     IF (EXPR(L5(1))>=0 AND EXPR(L5(1))<=9) THEN
      IF (EXPR(L5(2))>=0 AND EXPR(L5(2))<=9) THEN
       IF (EXPR(L5(3))>=0 AND EXPR(L5(3))<=9) THEN
        IF (EXPR(L5(4))>=0 AND EXPR(L5(4))<=9) THEN
         IF (EXPR(L5(5))>=0 AND EXPR(L5(5))<=9) THEN
          IF (EXPR(L5(6))>=0 AND EXPR(L5(6))<=9) THEN
           L8(0):=""+EXPR(L1(1))+EXPR(L1(2))+"° "+EXPR(L1(3))+EXPR(L1(4))+"."+EXPR(L1(5))+EXPR(L1(6))+EXPR(L1(7));
           L9(0):=""+EXPR(L1(8))+EXPR(L1(9))+EXPR(L1(10))+"° "+EXPR(L1(11))+EXPR(L1(12))+"."+EXPR(L1(13))+EXPR(L1(14))+EXPR(L1(15));
           L6(0):=TempList;
           Dist:=acos(sin(PublLat)*sin(FUNCDMTODEG(L8(SIZE(L8))))+cos(PublLat)*cos(FUNCDMTODEG(L8(SIZE(L8))))*cos(FUNCDMTODEG(L9(SIZE(L9)))-PublLon));
           IFERR(acos((sin(FUNCDMTODEG(L8(SIZE(L8))))-sin(PublLat)*cos(Dist))/(sin(Dist)*cos(PublLat)))) THEN
            L0(0):=ROUND(6371*π/180*Dist,-3)+" km  error°";
           ELSE
            θ:=360-acos((sin(FUNCDMTODEG(L8(SIZE(L8))))-sin(PublLat)*cos(Dist))/(sin(Dist)*cos(PublLat)));
            L0(0):=ROUND(6371*π/180*Dist,-3)+" km  "+ROUND(θ,0)+"°";
           END;
          END;
         END;
        END;
       END;
      END;
     END;
    END;
   END;
  END;
 END;
END;
END; 


I tried to build it recursively, but this is my first encounter with recursion so I can't find syntax which works.

I tried it with another approach where I packed everything as text and then I execute it via EXPR(...) and it works. Dissadvantage is unreadable code and everything must be in one string otherwise FOR and END will collapse.

Can anybody show me how build nested loops and IFs if I don't know their quantity beforehand?

Some screenshots: