Thread: Structure help.

Basically, I'm trying to define a structure type and I'm getting a syntax error on the third to last line.

Code:

struct term
{
 char sign;
 char coef;
 char xvar;
 char yvar;
 char oparen;
 term pterm[5]; //error here
 char cparen;
};

Also, on the same line I'm getting,

[Warning] no semicolon at the end of struct or union

I read in the tutorial on structures that the syntax for defining a structure type is different in C than C++, but when I comment out that line, it compiles fine. And, I know you can use a variable whose type is the structure you are defining, because it was done in the article on the Huffman compression technique.

Any thoughts?

BTW, I'm using the DevC++ compiler.

Code:

struct term
{
 char sign;
 char coef;
 char xvar;
 char yvar;
 char oparen;
 term pterm[5]; <--------
};

<---- The compiler doesn't know the storage requirement for struct term. So it will flag an error.
The only way around this is,

Code:

struct term
{
 char sign;
 char coef;
 char xvar;
 char yvar;
 char oparen;
 struct term* pterm;  
};

This works because, the size of a pointer type is constant ( for that particular OS and architecture ) and known before by the compiler.

Bah. Of course. Thankies.

Ah, nevermind. More errors. On that same line,

Code:

struct term pterm[5];

I'm now getting the error message,

field 'pterm' has incomplete type

But, wait! I changed the variable to a pointer and it works fine. Thanks.