getting global variables from dictionary

[icarus]

global_vars.py has the global variables
set_var.py changes one of the values on the global variables (don't
close it or terminate)
get_var.py retrieves the recently value changed (triggered right after
set_var.py above)

Problem: get_var.py retrieves the old value, the built-in one but not
the recently changed value in set_var.py.

What am I doing wrong?

----global_vars.py---
#!/usr/bin/python

class Variables :
def __init__(self) :
self.var_dict = {"username": "original username"}


---set_var.py ---
#!/usr/bin/python

import time
import global_vars

global_vars.Var iables().var_di ct["username"] = "new username"
time.sleep(10) #give enough time to trigger get_var.py


---get_var.py ---
#!/usr/bin/python
import global_vars
print global_vars.Var iables().var_di ct.get("usernam e")

[Aaron \Castironpi\ Brady]

Re: getting global variables from dictionary

On Sep 26, 9:01 pm, icarus <rsa...@gmail.c omwrote:

global_vars.py has the global variables
set_var.py changes one of the values on the global variables (don't
close it or terminate)
get_var.py retrieves the recently value changed (triggered right after
set_var.py above)
>
Problem: get_var.py retrieves the old value, the built-in one but not
the recently changed value in set_var.py.
>
What am I doing wrong?
>
----global_vars.py---
#!/usr/bin/python
>
class Variables :
        def __init__(self) :
                self.var_dict = {"username": "original username"}
>
---set_var.py ---
#!/usr/bin/python
>
import time
import global_vars
>
global_vars.Var iables().var_di ct["username"] = "new username"
time.sleep(10)   #give enough time to trigger get_var.py
>
---get_var.py ---
#!/usr/bin/python
import global_vars
print global_vars.Var iables().var_di ct.get("usernam e")

Are these separate processes?

[Chris Rebert]

Re: getting global variables from dictionary

When you do "Variables( )" in your code, you're making a new instance
of that class that has no relation to any other instances. This is the
cause of your problem. To just reference a class, use just
"Variables" . But that doesn't help in this case because var_dict is an
instance variable, not a class variable.

On Fri, Sep 26, 2008 at 7:01 PM, icarus <rsarpi@gmail.c omwrote:

global_vars.py has the global variables

No it doesn't, it just defines a class. The class itself (but NOT its
instances) is a module-level global.

set_var.py changes one of the values on the global variables (don't
close it or terminate)

No, it just instanciates the Variables class and then manipulates the
instance, which is then GC-ed because it's no longer referenced
anywhere, even in set_var.

get_var.py retrieves the recently value changed (triggered right after
set_var.py above)

No, it creates an entirely new instance of Variables and then fetches
the value from that instance (which is still using the default value
because this new instance has never been modified).

>
Problem: get_var.py retrieves the old value, the built-in one but not
the recently changed value in set_var.py.
>
What am I doing wrong?

Try just making var_dict a module-level variable in global_vars.py and
then manipulating that rather than this unnecessary mucking about with
Variables(). Alternatively, make var_dict a *class* variable of
Variables by removing it from __init__ and just putting 'var_dict =
{"username": "original username"}' in the raw class body of Variables;
And then remove the parentheses after Variables as I mentioned in the
beginning.

Regards,
Chris

>
----global_vars.py---
#!/usr/bin/python
>
class Variables :
def __init__(self) :
self.var_dict = {"username": "original username"}
>
>
---set_var.py ---
#!/usr/bin/python
>
import time
import global_vars
>
global_vars.Var iables().var_di ct["username"] = "new username"
time.sleep(10) #give enough time to trigger get_var.py
>
>
---get_var.py ---
#!/usr/bin/python
import global_vars
print global_vars.Var iables().var_di ct.get("usernam e")
--

http://mail.python.org/mailman/listinfo/python-list

>

--
Follow the path of the Iguana...

http://rebertia.com

[Ben Finney]

Re: getting global variables from dictionary

icarus <rsarpi@gmail.c omwrites:

global_vars.py has the global variables
set_var.py changes one of the values on the global variables (don't
close it or terminate)
get_var.py retrieves the recently value changed (triggered right after
set_var.py above)
>
Problem: get_var.py retrieves the old value, the built-in one but
not the recently changed value in set_var.py.

That's because you're making a new instance each time; each instance
carries its own state.

For a collection of attributes that should share state, probably the
simplest way is to use attributes of a module.

----global_vars.py---
#!/usr/bin/python
>
class Variables :
def __init__(self) :
self.var_dict = {"username": "original username"}

These aren't "global variables"; they still need to be imported, like
anything else from a module. Better to name the module by intent; e.g.
if these are configuration settings, a module name of 'config' might
be better.

Also, this module presumably isn't intended to be run as a program;
don't put a shebang line (the '#!' line) on files that aren't run as
programs.

===== config.py =====
# -*- coding: utf-8 -*-

# Name of the front-end user
username = "original username"

# Amount of wortzle to deliver
wortzle_amount = 170
=====

---set_var.py ---
#!/usr/bin/python
>
import time
import global_vars
>
global_vars.Var iables().var_di ct["username"] = "new username"
time.sleep(10) #give enough time to trigger get_var.py

===== set_config.py =====
# -*- coding: utf-8 -*-

import config

def set_user():
config.username = "new username"
=====

---get_var.py ---
#!/usr/bin/python
import global_vars
print global_vars.Var iables().var_di ct.get("usernam e")

===== get_config.py =====
# -*- coding: utf-8 -*-

import config

def get_user():
return config.username
=====


The 'config' module, imported by both of the other modules, maintains
state:

>>import config
>>print config.username

original username

>>import set_config
>>set_config.se t_user()
>>print config.username

new username

>>import get_config
>>print get_config.get_ user()

new username

--
\ “You can't have everything; where would you put it?” —Steven |
`\ Wright |
_o__) |
Ben Finney

[George Sakkis]

Re: getting global variables from dictionary

On Sep 26, 10:01 pm, icarus <rsa...@gmail.c omwrote:

global_vars.py has the global variables
set_var.py changes one of the values on the global variables (don't
close it or terminate)
get_var.py retrieves the recently value changed (triggered right after
set_var.py above)
>
Problem: get_var.py retrieves the old value, the built-in one but not
the recently changed value in set_var.py.
>
What am I doing wrong?
>
----global_vars.py---
#!/usr/bin/python
>
class Variables :
        def __init__(self) :
                self.var_dict = {"username": "original username"}
>
---set_var.py ---
#!/usr/bin/python
>
import time
import global_vars
>
global_vars.Var iables().var_di ct["username"] = "new username"
time.sleep(10)   #give enough time to trigger get_var.py
>
---get_var.py ---
#!/usr/bin/python
import global_vars
print global_vars.Var iables().var_di ct.get("usernam e")

First off, you don't import the set_var module anywhere; how do you
expect the value to change? Second, every time you do
"global_vars.Va riables()" you create a brand new Variables() instance,
initialized with the original var_dict. The Variables() instance you
create at set_var.py is discarded in the very next line. Third, I have
no idea why you put the "time.sleep(10) " there.

By the way, Python is not Java; you don't have to make classes for
everything. A working version of your example would be:

----global_vars.py---

var_dict = {"username": "original username"}

---set_var.py ---
import global_vars
global_vars.var _dict["username"] = "new username"

---get_var.py ---
import global_vars
import set_var
print global_vars.var _dict.get("user name")

$ python get_var.py
new username


HTH,
George