Index: src/infix2rpn.cxx
--- src/infix2rpn.cxx.orig
+++ src/infix2rpn.cxx
@@ -40,6 +40,7 @@ IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFT
 #include "string.hxx"
 #include "strlist.hxx"
 #include "strstack.hxx"
+using std::cerr;
 
 INFIX2RPN::INFIX2RPN()  {
 //nothin.
@@ -181,7 +182,7 @@ STRING TmpVal = "";
 
 //standardizes the various possible representations of
 //the various operators.
-CHR *INFIX2RPN::StandardizeOpName(const STRING op) {
+const char* INFIX2RPN::StandardizeOpName(const STRING op) {
         if ( (op ^= "AND") || (op == "&&") )
                 return "AND";
         else if ( (op ^= "OR") || (op == "||") )
@@ -200,7 +201,7 @@ CHR *INFIX2RPN::StandardizeOpName(const STRING op) {
 
 
 //converts the internal operator token name to a standard string
-CHR *INFIX2RPN::op2string(const operators op) {
+const char* INFIX2RPN::op2string(const operators op) {
         switch(op) {
                 case LeftParen:
                 case NOP: