[Python-ideas] Object for accessing identifiers/names

[Koos Zevenhoven]

Inspired by the discussions
regarding
 Guido's
​"M​
atch statement
​ brainstorm​
" and
​"​
Quick idea: defining variables from functions..." threads, here's an idea
regarding names/identifiers.

Currently, there is no direct way to work with variable names from within
Python. Yes, you can fiddle with __dict__s and locals() and globals(), but
there is no
​convenient ​
general way. To solve this, there could be a way
​(probably new syntax)​
 for creating an object that
​​
can examine and manipulate a name binding conveniently.

The object could be created for instance as follows:

​ ​
name_object = identifier some_name

However, 'identifier' is so long that I'll use the keyword 'def' instead,
regardless of whether it is optimal or not:

​  ​
name_obj = def some_name

Now this name_obj
​ thing​
could provide functionality like assigning to the name some_name, getting
the assigned object, and determining whether
​something has been assigned to the name or not
. The object would also be aware of the name 'some_name'.

​T
he functionality might
​work
 as follows:

​  ​
bool(
​name_obj
)
​   ​
# True if
​something​ is
 assigned to some_name
​  ​
name_obj.name()

​    ​
# == 'some_name'
​​
​  name_obj
.set(value) #
​equivalent to `some_name = value`​
​​
​  name_obj.get()      # equivalent to just `some_name​`
  name_obj.unset()    # like `del some_name`

​​Then you could pass this to a function:

  func(name_obj)

Now func will be able to assign to the variable some_name, but with
some_name referring to the scope where `name_obj = def some_name` was
executed. This is similar to things that can be done with closures.

This would also allow things like:

  if def some_name:
      #do stuff if the name some_name is bound to something

or

  if not def some_name:
      some_name = something()


- Koos
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