Programming Forums > Script Programming > Python

lrh9 · Jan 18th, 2010, 11:57 AM

I'm using the code module to add an interactive interpreter to an object. This object has an interact method that when called creates an interactive interpreter with the object's dictionary as the namespace for the interpreter.

When done interacting with the object, I want the "exit" function to return execution back to the original thread of execution.

Here is the initial code.

 Python Syntax (Toggle Plain Text) 
from uuid import uuid4
import code
 
ANONYMOUS = None
UUID = 0
 
class Agent:
 
    def __init__(self, name = UUID):
        self.__uuid = uuid4()
        if name == UUID:
            name = self.__uuid
        self.__name = name
 
 
    @property
    def uuid(self):
        return self.__uuid
 
 
    @property
    def name(self):
        return self.__name
 
    @name.setter
    def name(self, value):
        self.__name = value
 
    @name.deleter
    def name(self):
        self.__name = ANONYMOUS
 
    # The interactive interpreter.
    def interact(self):
        code.interact(local = self.__dict__)
from uuid import uuid4
import code

ANONYMOUS = None
UUID = 0

class Agent:

    def __init__(self, name = UUID):
        self.__uuid = uuid4()
        if name == UUID:
            name = self.__uuid
        self.__name = name


    @property
    def uuid(self):
        return self.__uuid


    @property
    def name(self):
        return self.__name

    @name.setter
    def name(self, value):
        self.__name = value

    @name.deleter
    def name(self):
        self.__name = ANONYMOUS

    # The interactive interpreter.
    def interact(self):
        code.interact(local = self.__dict__)

In the command prompt, calling the object's interact method and then calling the exit function results in a complete exit, but using ctrl+z and return returns the thread of execution to the original interpreter.

In the IDLE GUI interpreter, calling the object's interact method and then calling the exit function results in a complete exit, and ctrl+z and return only erases the last input or output.

So I'm open to suggestions. If possible I'd like to avoid redefining the exit function.

My first instinct was to catch the SystemExit exception in the interact function and return. This works well in the command prompt. However, it still results in a complete exit in the IDLE GUI interpreter.

 Python Syntax (Toggle Plain Text) 
def interact(self):
        try:
            code.interact(local = self.__dict__)
        except SystemExit:
            return
def interact(self):
        try:
            code.interact(local = self.__dict__)
        except SystemExit:
            return

I have one tangent question about this. The object's attributes and methods not in the object's dictionary are obviously not accessible in the new interpreter. (In this case the property functions and the interact function.) This isn't a problem at the moment because I cannot think of any compelling reason why they should be accessible, and variables and functions defined in the new interpreter will be accessible from the object once the interpreter exits. If I did want these attributes and methods to be accessible though, what would be the best way to do it?

Thank you for reading this.

lrh9 · Jan 18th, 2010, 12:20 PM

I was able to answer my last question.

In order to access all of the attributes of the object simply pass locals() as the local, and then refer to the object as "self".

woooee · Jan 19th, 2010, 10:53 AM

Quote:

return execution back to the original thread

Are you using multiprocessing or threading? The 'standard' way is to exit/kill the process.

lrh9 · Jan 19th, 2010, 11:54 AM

Neither. The code module's interpreter is merely an emulator of the Python interpreter. In simple terms, it starts an input loop that executes input as code - in the fashion of the Python interpreter.

Unfortunately, the only way to interrupt this loop as far as I know without redefining it is to use the exit function. Instead of exiting, I want to go back to the original interpreter.

woooee · Jan 19th, 2010, 1:12 PM

Can you put the code under a while loop and set a variable to 'False' when you want to exit instead of calling sys.exit(), or return from a function?

lrh9 · Jan 20th, 2010, 3:09 PM

I would have liked the intuitive command for exiting an interpreter to be the command for exiting this interpreter emulator.

Jan 18th, 2010, 11:57 AM	#1
lrh9 Professional Programmer Join Date: Nov 2008 Posts: 305 Rep Power: 2	Problems with the interpreter's exit() function. I'm using the code module to add an interactive interpreter to an object. This object has an interact method that when called creates an interactive interpreter with the object's dictionary as the namespace for the interpreter. When done interacting with the object, I want the "exit" function to return execution back to the original thread of execution. Here is the initial code. Python Syntax (Toggle Plain Text) from uuid import uuid4 import code ANONYMOUS = None UUID = 0 class Agent: def __init__(self, name = UUID): self.__uuid = uuid4() if name == UUID: name = self.__uuid self.__name = name @property def uuid(self): return self.__uuid @property def name(self): return self.__name @name.setter def name(self, value): self.__name = value @name.deleter def name(self): self.__name = ANONYMOUS # The interactive interpreter. def interact(self): code.interact(local = self.__dict__) from uuid import uuid4 import code ANONYMOUS = None UUID = 0 class Agent: def __init__(self, name = UUID): self.__uuid = uuid4() if name == UUID: name = self.__uuid self.__name = name @property def uuid(self): return self.__uuid @property def name(self): return self.__name @name.setter def name(self, value): self.__name = value @name.deleter def name(self): self.__name = ANONYMOUS # The interactive interpreter. def interact(self): code.interact(local = self.__dict__) In the command prompt, calling the object's interact method and then calling the exit function results in a complete exit, but using ctrl+z and return returns the thread of execution to the original interpreter. In the IDLE GUI interpreter, calling the object's interact method and then calling the exit function results in a complete exit, and ctrl+z and return only erases the last input or output. So I'm open to suggestions. If possible I'd like to avoid redefining the exit function. My first instinct was to catch the SystemExit exception in the interact function and return. This works well in the command prompt. However, it still results in a complete exit in the IDLE GUI interpreter. Python Syntax (Toggle Plain Text) def interact(self): try: code.interact(local = self.__dict__) except SystemExit: return def interact(self): try: code.interact(local = self.__dict__) except SystemExit: return I have one tangent question about this. The object's attributes and methods not in the object's dictionary are obviously not accessible in the new interpreter. (In this case the property functions and the interact function.) This isn't a problem at the moment because I cannot think of any compelling reason why they should be accessible, and variables and functions defined in the new interpreter will be accessible from the object once the interpreter exits. If I did want these attributes and methods to be accessible though, what would be the best way to do it? Thank you for reading this. __________________ IT'S int main() DAMN IT!!! Chronic sufferer of fancy programming syndrome.

Jan 18th, 2010, 12:20 PM	#2
lrh9 Professional Programmer Join Date: Nov 2008 Posts: 305 Rep Power: 2	Re: Problems with the interpreter's exit() function. I was able to answer my last question. In order to access all of the attributes of the object simply pass locals() as the local, and then refer to the object as "self". __________________ IT'S int main() DAMN IT!!! Chronic sufferer of fancy programming syndrome. Last edited by lrh9; Jan 18th, 2010 at 12:32 PM.

Jan 19th, 2010, 11:54 AM	#4
lrh9 Professional Programmer Join Date: Nov 2008 Posts: 305 Rep Power: 2	Re: Problems with the interpreter's exit() function. Neither. The code module's interpreter is merely an emulator of the Python interpreter. In simple terms, it starts an input loop that executes input as code - in the fashion of the Python interpreter. Unfortunately, the only way to interrupt this loop as far as I know without redefining it is to use the exit function. Instead of exiting, I want to go back to the original interpreter. __________________ IT'S int main() DAMN IT!!! Chronic sufferer of fancy programming syndrome.

Jan 19th, 2010, 1:12 PM	#5
woooee Programmer Join Date: Jun 2008 Posts: 34 Rep Power: 0	Re: Problems with the interpreter's exit() function. Can you put the code under a while loop and set a variable to 'False' when you want to exit instead of calling sys.exit(), or return from a function? __________________ Linux counter #99383

Jan 20th, 2010, 3:09 PM	#6
lrh9 Professional Programmer Join Date: Nov 2008 Posts: 305 Rep Power: 2	Re: Problems with the interpreter's exit() function. I would have liked the intuitive command for exiting an interpreter to be the command for exiting this interpreter emulator. __________________ IT'S int main() DAMN IT!!! Chronic sufferer of fancy programming syndrome.

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Programming Forums > Script Programming > Python

Problems with the interpreter's exit() function.