typedef struct { int b_type; /* what kind of block this is */ int b_handler; /* where to jump to find handler */ int b_level; /* value stack level to pop to */ } PyTryBlock;
typedef struct _frame { PyObject_VAR_HEAD struct _frame *f_back; /* previous frame, or NULL */ PyCodeObject *f_code; /* code segment */ PyObject *f_builtins; /* builtin symbol table (PyDictObject) */ PyObject *f_globals; /* global symbol table (PyDictObject) */ PyObject *f_locals; /* local symbol table (any mapping) */ PyObject **f_valuestack; /* points after the last local */ /* Next free slot in f_valuestack. Frame creation sets to f_valuestack. Frame evaluation usually NULLs it, but a frame that yields sets it to the current stack top. */ PyObject **f_stacktop; PyObject *f_trace; /* Trace function */
/* If an exception is raised in this frame, the next three are used to * record the exception info (if any) originally in the thread state. See * comments before set_exc_info() -- it's not obvious. * Invariant: if _type is NULL, then so are _value and _traceback. * Desired invariant: all three are NULL, or all three are non-NULL. That * one isn't currently true, but "should be". */ PyObject *f_exc_type, *f_exc_value, *f_exc_traceback;
PyThreadState *f_tstate; int f_lasti; /* Last instruction if called */ /* Call PyFrame_GetLineNumber() instead of reading this field directly. As of 2.3 f_lineno is only valid when tracing is active (i.e. when f_trace is set). At other times we use PyCode_Addr2Line to calculate the line from the current bytecode index. */ int f_lineno; /* Current line number */ int f_iblock; /* index in f_blockstack */ PyTryBlock f_blockstack[CO_MAXBLOCKS]; /* for try and loop blocks */ PyObject *f_localsplus[1]; /* locals+stack, dynamically sized */ } PyFrameObject;