include xpllib;         \provides StrLen, ToLower, StrCopy, and StrCmp

proc StrToLower(A, B);
char A, B, I;
for I:= 0 to StrLen(B) do A(I):= ToLower(B(I));

proc CompareStrings(A, B, Sens);
char A, B, Sens, C, D;
[C:= Reserve(StrLen(A)+1);
 D:= Reserve(StrLen(B)+1);
Text(0, "Comparing "); Text(0, A); Text(0, " and "); Text(0, B); Text(0, ", ");
if Sens then
        [Text(0, "case sensitively:^m^j");
        StrCopy(C, A);
        StrCopy(D, B);
        ]
else    [Text(0, "case insensitively:^m^j");
        StrToLower(C, A);
        StrToLower(D, B);
        ];
Text(0, "    ");  Text(0, A);  Text(0, " <  ");  Text(0, B);  Text(0, " -> ");
Text(0, if StrCmp(C, D) < 0 then "true" else "false");  CrLf(0);
Text(0, "    ");  Text(0, A);  Text(0, " >  ");  Text(0, B);  Text(0, " -> ");
Text(0, if StrCmp(C, D) > 0 then "true" else "false");  CrLf(0);
Text(0, "    ");  Text(0, A);  Text(0, " =  ");  Text(0, B);  Text(0, " -> ");
Text(0, if StrCmp(C, D) = 0 then "true" else "false");  CrLf(0);
Text(0, "    ");  Text(0, A);  Text(0, " #  ");  Text(0, B);  Text(0, " -> ");
Text(0, if StrCmp(C, D) # 0 then "true" else "false");  CrLf(0);
Text(0, "    ");  Text(0, A);  Text(0, " <= ");  Text(0, B);  Text(0, " -> ");
Text(0, if StrCmp(C, D) <= 0 then "true" else "false");  CrLf(0);
Text(0, "    ");  Text(0, A);  Text(0, " >= ");  Text(0, B);  Text(0, " -> ");
Text(0, if StrCmp(C, D) >= 0 then "true" else "false");  CrLf(0);
CrLf(0);
];

[CompareStrings("cat", "dog", true);
 CompareStrings("Rat", "RAT", true);
 CompareStrings("Rat", "RAT", false);
 CompareStrings("1100", "200", true);
]