Import if condition is correct

[MindClass]

Is possible import a library according to a condition?

if Foo = True:
import bar

 

[Georg Brandl]

Is possible import a library according to a condition?

if Foo = True:
import bar

Why don't you try it?

(in the above code, not the import is the problem, but using the
assignment operator in an expression)

Georg

 

[MindClass]

Why don't you try it?

I thinked that could be another way for import statement.

In that case I'll have to set a global variable before of the import
statements although I'd prefer not use them.

 

[Steve Holden]

I thinked that could be another way for import statement.

In that case I'll have to set a global variable before of the import
statements although I'd prefer not use them.

I'm guessing that you think this might be necessary to avoid importing
the same module multiple times: it's not. Python only runs the module's
code the first time the module is imported into a program. A further
import statement effectively does noting, because the interpreter sees
(from an entry in the sys.modules dictionary) that the module is already
present.

regards
Steve

 

[MindClass]

I'm guessing that you think this might be necessary to avoid importing
the same module multiple times: it's not. Python only runs the module's
code the first time the module is imported into a program. A further
import statement effectively does noting, because the interpreter sees
(from an entry in the sys.modules dictionary) that the module is already
present.

The problem is that I've to import different libraries according to the
ORM (SQLObject, SQLAlchemy, etc)

 

[Steve Holden]

The problem is that I've to import different libraries according to the
ORM (SQLObject, SQLAlchemy, etc)

So why the need for global variables?

if MySQL_wanted:
import MySQLdb as db
elif sqlite_wanted:
import pysqlite as db
else:
import psycopg2 as db

conn = db.connect(...)
....

regards
Steve

 

[Bruno Desthuilliers]

Is possible import a library according to a condition?

if Foo = True:
import bar

Did you even try ? Would have been faster than posting here...