Ola Natvig wrote:
Olivier Noblanc ATOUSOFT wrote:
Hello
What is the equivalent function of php isset() in python
try:
if variable:
# isset
pass
except NameError:
# not set
pass
you could use:
>>> 'variable' in vars()
But be aware that it is bad bad practice to do it like that.
If you need variables that you don't know that name of, you should put them in a dictionary. They are made for that exact purpose.
>>> unkown_vars = {} >>> unkown_vars['variable'] = 42 >>> 'variable' in unkown_vars True
If it's a greater possibility that the 'variable' are set than it's not you will get better performance when using:
try:
print unknown_vars['variable']
except KeyError:
print 'variable are not set'istead of
if 'variable' in unknown_vars:
print unknown_vars['variable']
else:
print 'variable are not set'You could even use
print unknown_vars.get('variable', 'variable are not set')dictionary.get(key, default) returns the default if key are not located in the dictionary, I'm not sure if the function uses the try / except KeyError aproach or what it uses.
-- -------------------------------------- Ola Natvig <[EMAIL PROTECTED]> infoSense AS / development -- http://mail.python.org/mailman/listinfo/python-list
