List user defined variables, python

Question

I am trying to iterate through the variables set in a python script. I came across the following:

Enumerate or list all variables in a program of [your favorite lang

Answer 1

I wanted something more along the lines of matlab 'whos', so I baked this up: gist here

import __main__
def whos(lss):
 fil = __main__.__file__
 thisthinghere = open(fil).read().split("\n")
 vs = []
 for l in thisthinghere:
    if l.find("=") > -1:
        vs.append(l.split("=")[0].strip())
 keys = lss.keys()
 out = {}
 for v in vs:
    try: 
        out[v] = lss[v]
    except:
        "not in list"
 keys = out.keys()
 keys.sort()
 for k in keys:
    val = str(out[k])
    if len (val) > 10:
        if val[-1] == ")":val = val[0:10]+"..."+val[-10:]
        elif val[-1] == "]" :val = val[0:10]+"..."+val[-10:]
        else: val = val[0:10]
    print k,":",val

 return out

#import into your script and call with whos(locals())

it seems to work. it will print the variable space, and it returns it as a dictionary for easy pickling/jsoning.

Answer 2

You can strip out variables that are included in your module by default by checking if they are in the builtin __builtins__ module, like this:

>>> x = 3
>>> set(dir()) - set(dir(__builtins__))
set(['__builtins__', 'x'])

The only thing this doesn't strip out is __builtins__ itself, which is easy to special case.

Also note that this won't work if you have re-defined any builtin names. You shouldn't do this in practice, but a lot of people do, many by accident.

Answer 3

Here is solution.

#!/us/bin/python    

not_my_data = set(dir())

foo1 = "Hello world"
foo2 = "bar"
foo3 = {"1":"a", "2":"b"}
foo4 = "1+1"

my_data = set(dir()) - not_my_data

for name in my_data :
    myvalue = eval(name)
    print name, "is", type(name), "and is equal to ", myvalue

but this is bad practice.

You should use something like

#!/us/bin/python    
my_data = dict()                                                                                   
my_data['foo1'] = "Hello world"
my_data['foo2'] = "bar"
my_data['foo1'] = {"1":"a", "2":"b"}
my_data['foo1'] = "1+1"

for name in my_data :
    myvalue = eval(my_data[name])
    print name, "is", type(name), "and is equal to ", myvalue

Answer 4

The question title leads me to see this. But this is not what I wanted.

self-answering is below

[s for s in dir() if not '__' in s]

Answer 5

If you don't put any underscores in front of your variables you could do:

#!/us/bin/python                                                                                    

foo1 = "Hello world"
foo2 = "bar"
foo3 = {"1":"a", "2":"b"}
foo4 = "1+1"

for name in dir():
    if not name.startswith('__'):
        myvalue = eval(name)
        print name, "is", type(myvalue), "and is equal to ", myvalue