GiNaC/ginac print.h ...

[Christian Bauer]

Hi!

On Sat, Apr 07, 2001 at 05:18:42PM +0200, Pearu Peterson wrote:
> For example, by a special print_context object, say,
> print_callback, that contains an user-defined function

This doesn't sound different from a general tree-traversal function like
this one:

  static void traverse(const ex & e)
  {
      cout << e.bp->class_name() << "(";
      unsigned n = e.nops();  
      if (n)
          for (unsigned i=0; i<n; i++) {
              traverse(e.op(i));
              if (i != n-1)   
  	          cout << ",";
          }
      else
          cout << "'" << e << "'";
      cout << ")"; 
  }

"traverse(pow(2, n) + 3)" will produce

  add(power(numeric('2'),symbol('n')),numeric('3'))

The traverse() function needs further refinement because some classes have
additional properties that are not accessible via op() (the most noticable
error is that all functions are printed as "function(...)" instead of with
their real name; and there doesn't seem to be a way to get the name from a
function object (this will be corrected shortly)), but basically it seems
to be what you want.

Bye,
Christian

-- 
  / Coding on PowerPC and proud of it
\/ http://www.uni-mainz.de/~bauec002/