[Crowe182]

I have written a program for class that acts like a phone. It will read a file from my hard driver and then out put if it is a valid number. I have declared a function that passes the value of each digit in the number and then checks that number as valid, how ever it goes in as a char but returns a 0 is valid or -1 if not valid and those are an int. This is the error I get when I invoke the function:

"C:\C++ 2\Lab2.cpp(65) : error C2664: 'to_digit' : cannot convert parameter 1 from 'char' to 'int &'
A reference that is not to 'const' cannot be bound to a non-lvalue"

And this is the code of the function and the additional function I invoked inside.

char read_dials(ifstream& infile ,char &c1,char &c2,char &c3,char &c4,char &c5,char &c6,char &c7,char &c8)

{

	infile>>c1>>c2>>c3>>c4>>c5>>c6>>c7>>c8;
	if ((to_digit(c1)==-1)||(to_digit(c2)==-1)||(to_digit(c3)==-1)||(to_digit(c4)==-1)||(to_digit(c5)==-1)||(to_digit(c6)==-1)||(to_digit(c7)==-1)||(to_digit (c8)==-1))
		return -1;
	if (c1=='0')
		return -2;
	if ((c1=='5')&&(c2=='5')&&(c3=='5'))
		return -3;
	if (c4 != '-')
		return -4;
	if((c1=='-')||(c2=='-')||(c3=='-')||(c5=='-')||(c6=='-')||(c7=='-')||(c8=='-'))
		return -4;
	if(infile.eof())
		return 0;
}
int to_digit(int& c)
{
	switch (toupper(c))
	{
	case '0':
		c=0;
		return 0;
	case '1':
		c=1;
		return 0;
	case '2': case 'A': case 'B': case 'C':
		c=2;
		return 0;
	case '3': case 'D': case 'E': case 'F':
		c=3;
		return 0;
	case '4': case 'G': case 'H': case 'I':
		c=4;
		return 0;
	case '5': case 'J': case 'K': case 'L':
		c=5;
		return 0;
	case '6': case 'M': case 'N': case 'O':
		c=6;
		return 0;
	case '7': case 'P': case 'R': case 'S':
		c=7;
		return 0;
	case '8': case 'T': case 'U': case 'V':
		c=8;
		return 0;
	case '9': case 'W': case 'X': case 'Y':
		c=9;
		return 0;
	default:
		return -1;
	}

The line where the error is, is on this line:
if ((to_digit(c1)==-1)||(to_digit(c2)==-1).......(c8)==-1))

How do I resolve this error....

[AlbertB]

Your function "to_digit" performs its actions on a char which is passed in as 'c'. However you are trying to pass in the address of c - '&c'. Poor thing is confused!


int to_digit(int c) // Note '&' has been removed.
{
switch (toupper(c))
etc



You will also need to make sure that all control paths are returning a value in your "read_dials" function. Add something like:

else
return 1;

to the end as a 'catchall'.

[Crowe182]

Ok great, that worked...Thanks man, this one has whipped my butt..
One more problem...This error comes up:

"Compiling...
Lab2.cpp
C:\C++ 2\Lab2.cpp(76) : warning C4715: 'read_dials' : not all control paths return a value"

It comes from my read_dials function. What do I need to do to have the return value come up and have the value that is passed to the to_digits function replaced by the switch's case value.

[Crowe182]

Ok just read the last of your message, where will I put the return value in read_dials?

[Crowe182]

Great thanks, I got it to work now, and with the help of the debugger.

You guys rock, thanks again!!!!

[AlbertB]

Pleased to help Crowe.

If it has solved your problem can you make a point of editing the title of the thread to add on:

" - solved"