Using & in #define

I am trying to use some code from Ronald Mak's Writing Compilers & Interpreters:

Code:

---

#define enter_name_local_symtab(name, &symtab_display[level])  \
  idp = enter_symtab(name, &symtab_display[level])

---

and this comes up with an error
"&" cannot be used in a macro parameter list. I note that this is used quite a bit in the book (the book is quite old, so the C will be outdated).

How do I get over this?

You put the complexity in when you call the macro, not when you declare it.

Code:

---

#define enter_name_local_symtab(a, b)  \
  idp = enter_symtab(a,b)

// then later, use the macro
enter_name_local_symtab(name, &symtab_display[level])

---

The macro parameters are just placeholders, to be replaced literally with the values used when you call the macro.

Have a look at: ftp://ftp.dante.de/tex-archive/support/ltx2x/l2xisymt.h where it has:

Code:

---

/**************************************************************************/
/* enter_name_local_symtab() enter the given name into the local symtab  */
/*                      and set pointer to the entry                      */
#define enter_name_local_symtab(idp, name)                    \
  idp = enter_symtab(name, &symtab_display[level])
/**************************************************************************/

---

I don't particularly like that very much at all but it will at least work assuming there is a variable 'level' in scope (that's the stupid part I don't like)

Thank you Salem and Hodor. I'll look at your suggestions and see how they work before I progress further.