Convert the string to the variable name in Python (2023)

Convert the string to the variable name in Python

x='buffalo'
exec("%s = %d" % (x,2))

After that you can check it by:

buffalo print

As output you see:
2

Convert a string to a variable name in Python

I just made a quick example to do what you want to do. I don't recommend you to do this, but I assume you have a good reason for doing so and will help you.

Variablen = ["a", "b", "c"]
for i in range(len(vars)):
globalis()[vars[i]] = (i+1)*10
Print(a) #10
Print(b) #20
Print (c) No. 30

This example can be a bit complicated but it does exactly what you asked for in your question, in short you can use the globals() function to convert a string to a variable. Link to more information here: https://www.pythonpool.com/python-string-to-variable-name/

Convert variable names to string?

TL;DR: That's not possible. See "Conclusion" at the end.

There is one usage scenario where you might need this. I'm not suggesting that there aren't better ways or that they achieve the same functionality.

This would be useful for accidentally "downloading" an arbitrary list of dictionaries, in debugging modes and other similar situations.

What would be needed is the inverse ofEvaluation()Function:

get_identifier_name_missing_function()

which would take an identifier name ('variable', 'dictionary', etc.) as an argument and return a
String containing the name of the identifier.

Consider the following current situation:

random function (data argument)

If you pass an identifier name ('function', 'variable', 'dictionary', etc.)data argumentfor onerandom_function()(another identifier name), you actually pass an identifier (for example:<argument data object at 0xb1ce10>) to another identifier (for example:<Random function function at 0xafff78>):

<random function function at 0xafff78>(<argument data object at 0xb1ce10>)

As I understand it, only the memory address is passed to the function:

<function at 0xafff78>(<object at 0xb1ce10>)

Therefore, it would be necessary to pass a string as an argument torandom_function()then this function has the name of the argument identifier:

random_function('Datenargument')

Inside the random() function

def random_function(erstes_argument):

, one would use the string already provided'data argument'for:

1. serve as an 'identifier name' (for viewing, logging, splitting/concatenating strings, etc.)

   (Video) Python Lesson 4 - Getting Input from the User, Converting Variable Types

2. EssenEvaluation()Function to get a reference to the actual identifier and thus a reference to the actual data:

   print("currently being processed", first_argument)
   some_internal_variable = eval(erstes_argument)
   print("Here comes the data: " + str(some_internal_var))
   

Unfortunately, this does not work in all cases. It only works if therandom_function()can solve that'data argument'String to a real identifier. I mean yesdata argumentthe name of the identifier is available inrandom_function()of the namespace.

Isn't always like this:

# principal1.py
importar some_module1
data_argument = 'my data'
some_module1.random_function('argument_data')
# algun_modulo1.py
def random_function(erstes_argument):
print("currently being processed", first_argument)
some_internal_variable = eval(erstes_argument)
print("Here comes the data: " + str(some_internal_var))
######

The expected results would be:

Work in progress: argument_data
here comes the data: my data

Weildata argumentthe identifier name is not available inrandom_function()namespace of , this would result in:

Currently working on argument_data
Trace (last most recent call):
File "~/main1.py", line 6, in <module>
some_module1.random_function('argument_data')
File "~/some_module1.py", line 4, in random_function
some_internal_variable = eval(erstes_argument)
File "<string>", line 1, in <module>
NameError: Name "argument_data" is not defined

Now consider the hypothetical use of aget_identifier_name_missing_function()which would behave as described above.

Here is a dummy Python 3.0 code: .

# principal2.py
import some_module2
some_dictionary_1 = { 'definition_1':'text_1',
'definition_2':'text_2',
'etc. and so forth.' }
some_other_dictionary_2 = { 'key_3':'value_3',
'key_4':'value_4',
'etc. and so forth.' }
#
# more stuff like that
#
some_other_dictionary_n = { 'random_n':'random_n',
'etc. and so forth.' }
for each_my_dictionaries in (any_dictionary_1,
some_other_dictionary_2,
...,
some_other_dictionary_n ):
some_module2.some_function(each_of_my_dictionaries)
# algun_modulo2.py
def some_function(a_dictionary_object):
für _clave, _valor und a_dictionary_object.items():
print(get_indentifier_name_missing_function(a_dictionary_object) +
" " +
string (_key) +
" = " +
string (_value) )
######

The expected results would be:

some_dictionary_1 definition_1 = text_1
some_dictionary_1 definition_2 = text_2
some_dictionary_1 etc = etc .
some_other_dictionary_2 key_3 = value_3
some_other_dictionary_2 key_4 = value_4
some_other_dictionary_2 etc = etc .
......
......
......
some_other_dictionary_n random_n = random_n
some_other_dictionary_n etc = etc .

unfortunately,get_identifier_name_missing_function()You would not see the names of the 'original' identifiers (any_dictionary_,other_dictionary_2,some_other_dictionary_n). I would only see thema_dictionary_objectidentifier name.

So the actual result would be:

a_dictionary_object definition_1 = text_1
a_dictionary_object definition_2 = texto_2
a_dictionary_object etc = etc.
a_dictionary_object chave_3 = valor_3
a_dictionary_object clave_4 = valor_4
a_dictionary_object etc = etc.
......
......
......
a_dictionary_object random_n = random_n
a_dictionary_object etc = etc.

So vice versaEvaluation()The function is not that useful in this case.

Currently you would need to do the following:

# main2.py as above except:
for each_one_of_my_name_dictionaries in('some_dictionary_1',
'another_dictionary_2',
'...',
'some_other_dictionary_n'):
some_module2.some_function( { each_one_of_my_dictionaries_names :
eval(any_one_of_my_dictionary_names) } )
# algun_modulo2.py
def some_function(a_dictionary_name_object_container):
para _dictionary_name, _dictionary_object em a_dictionary_name_object_container.items():
für _key, _value in _dictionary_object.items():
print(str(_dictionary_name) +
" " +
string (_key) +
" = " +
string (_value) )
######

Complete:

• Python only passes memory addresses as arguments to functions.
• Strings representing the name of an identifier can only be referred to by the actual identifierEvaluation()Function if the name identifier is available in the current namespace.
• A hypothetical reversal ofEvaluation()function, it wouldn't make sense in cases where the calling code doesn't directly "see" the name of the identifier. For example. within each called function.
• Currently you need to pass a function:
  
  1. the string representing the name of the identifier
  2. the real identifier (memory address)

This can be achieved by passing both'corda'mieval('string')at the same time as the called function. I think this is the most "general" way to solve this chicken egg problem in any function, module and namespace without using corner case solutions. The only downside is usingEvaluation()Feature that can easily lead to unsafe code. Care should be taken not to feed themEvaluation()work with almost anything, especially unfiltered external input data.

How to convert a string to a variable name in Python

You can enter the variables directlyglobal:

x = ['recursive1','recursive2']
to varname in x:
globals()[Variablenname] = 123
Print (Source1)
#123

This allows you to createjas stated in the question.

Just because it's possible doesn't mean it should be done that way. Without knowing the details of the problem to solve, it's difficult to give better advice, but there might be a better way to get what you're looking for.

Update: In a comment, @mozway raised some concerns about the above, one of which was thisjIt is not changed if, for example, Function2 is changed. For example:

x = ['recursive1','recursive2']
to varname in x:
globals()[Variablenname] = 123
y = [Resource1, Resource2]
print(s)
#[123, 123]
Feature2 = 456
print(s)
#[123, 123]

This seems useful, although I got similar behavior myself with the regular syntax:

Resource1 = 123
Feature2 = 123
y = [Resource1, Resource2]
print(s)
#[123, 123]
Feature2 = 456
print(s)
#[123, 123]

How to convert a string to a valid variable name in Python?

According to Python, an identifier is a letter or underscore followed by an unlimited sequence of letters, numbers, and underscores:

import right
Final cleaning(s):
# Remove invalid characters
s = re.sub('[^0-9a-zA-Z_]', '', s)
# Remove leading characters until we find a letter or underscore
s = re.sub('^[^a-zA-Z_]+', '', s)
returns

Use like this:

>>> limpiar(' 32v2 g #Gmw845h$W b53wi ')
'v2gGmw845hWb53wi'

Convert a string to pre-existing variable names

As mentioned in the StackOverflow questionConfigParser local override, you are looking forEvaluation():

print eval('self.post.id') # Print a value of self.post.id

How to use a string value as a variable name in Python?

I don't understand exactly what you're trying to achieve with this, but it can be done withEvaluation. I do not recommend using itEvaluationHowever. It would be better if you finally tell us what you want to achieve.

>>> Karamell = ['a','b','c']
>>> fruit = ['d','e','f']
>>> Boot = ['g','h','i']
>>> name = 'fruit'
>>> evaluate(name)
['d', 'e', ​​​​'f']

EDIT

See the other answer by Sнаđошƒаӽ. There will be a better way.Evaluationit poses a security risk and I do not recommend its use.

How do I convert a string to a variable name?

Here is a suitable solution that matches what you are trying to do (which I believe is letter indexing) using dictionaries:

Result = {}
ord = input() # Why are you calling this variable ord?
count = 1
for i in order:
if not in the result:
result[i] = []
result[i].attachment(count)
count += 1
Print (Result)

No Vars, no locals, noperishwith an uncertain context. It's no problem if someone writesUEon your input and other similar problems. Everything safe and easy. It can be further simplified with defaultdict.

As a side note: forget about the existence of vars/locals/globals and similar objects. I've never had to use them even though I've been programming in Python for a decade. This is interesting when you write crazy code like a Python debugger. Otherwise it is not necessary. And these are swords that will cut you unless you are a samurai.

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