TPython

Function Members (Methods)

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public:

	TPython()
	TPython(const TPython&)
virtual	~TPython()
static Bool_t	Bind(TObject* object, const char* label)
static TClass*	Class()
static const TPyReturn	Eval(const char* expr)
static void	Exec(const char* cmd)
static void	ExecScript(const char* name, int argc = 0, const char** argv = "0")
virtual TClass*	IsA() const
static void	LoadMacro(const char* name)
TPython&	operator=(const TPython&)
static void	Prompt()
virtual void	ShowMembers(TMemberInspector& insp, char* parent)
virtual void	Streamer(TBuffer& b)
void	StreamerNVirtual(TBuffer& b)

private:

static Bool_t

Initialize()

Class Description

                          Python interpreter access
                          =========================

 The TPython class allows for access to python objects from CINT. The current
 functionality is only basic: ROOT objects and builtin types can freely cross
 the boundary between the two interpreters, python objects can be instantiated
 and their methods can be called. All other cross-coding is based on strings
 that are run on the python interpreter.

 Examples:

  $ cat MyPyClass.py
  print 'creating class MyPyClass ... '

  class MyPyClass:
     def __init__( self ):
        print 'in MyPyClass.__init__'

     def gime( self, what ):
        return what

  $ root -l
  // Execute a string of python code.
  root [0] TPython::Exec( "print \'Hello World!\'" );
  Hello World!

  // Create a TBrowser on the python side, and transfer it back and forth.
  // Note the required explicit (void*) cast!
  root [1] TBrowser* b = (void*)TPython::Eval( "ROOT.TBrowser()" );
  root [2] TPython::Bind( b, "b" );
  root [3] b == (void*) TPython::Eval( "b" )
  (int)1

  // Builtin variables can cross-over by using implicit casts.
  root [4] int i = TPython::Eval( "1 + 1" );
  root [5] i
  (int)2

  // Load a python module with a class definition, and use it.
  root [6] TPython::LoadMacro( "MyPyClass.py" );
  creating class MyPyClass ...
  root [7] MyPyClass m;
  in MyPyClass.__init__
  root [8] char* s = m.gime( "aap" );
  root [9] s
  (char* 0x41ee7754)"aap"

 It is possible to switch between interpreters by calling "TPython::Prompt()"
 on the CINT side, while returning with ^D (EOF). State is preserved between
 successive switches.

void ExecScript( const char* name, int argc, const char** argv )

 Execute a python stand-alone script, with argv CLI arguments.

 example of use:
    const char* argv[] = { "1", "2", "3" };
    TPython::ExecScript( "test.py", sizeof(argv)/sizeof(argv[0]), argv );

const TPyReturn Eval( const char* expr )

 Evaluate a python expression (e.g. "ROOT.TBrowser()").

 Caution: do not hold on to the return value: either store it in a builtin
 type (implicit casting will work), or in a pointer to a ROOT object (explicit
 casting to a void* is required).

TPython

class TPython

Function Members (Methods)

Class Description