Anusree Anilkumar's Blog
The dir() Function in python

The dir() Function in python

Anusree Anilkumar's photo
Anusree Anilkumar
·

2 min read

Introduction

The dir() method tries to return a list of valid attributes of the object, without the values. the dir() function is a built-in function that lists the identifiers defined in the module. These modules may include functions, classes, and variables.

Syntax

The syntax of dir() function is

dir([object])

Examples

print(dir())

// Output: ['__annotations__', '__builtins__', '__doc__', '__loader__', 
'__name__', '__package__', '__spec__']

If a module name is defined in the dir() function, it will return the list of modules in that module 👇

def print_var(x):
    print(x)
x=18
print_var(x)
print(dir(print_var))

// Output: 18
['__annotations__', '__call__', '__class__', '__closure__', '__code__', 
'__defaults__', '__delattr__', '__dict__', '__dir__', '__doc__', '__eq__', 
'__format__', '__ge__', '__get__', '__getattribute__', '__globals__',
 '__gt__', '__hash__', '__init__', '__init_subclass__', '__kwdefaults__', 
'__le__', '__lt__', '__module__', '__name__', '__ne__', '__new__',
 '__qualname__', '__reduce__', '__reduce_ex__', '__repr__', 
'__setattr__', '__sizeof__', '__str__', '__subclasshook__']

If no name is specified, the dir() will return the list of modules defined in the current module 👇

list1 = []
a= 10;
print(dir())

// Output: ['__annotations__', '__builtins__', '__doc__', '__loader__',
 '__name__', '__package__', '__spec__', 'a', 'list1']

It shows the functions belonging to math module 👇

import math
print(dir(math))

//Output: ['__doc__', '__loader__', '__name__', '__package__', '__spec__', 
'acos', 'acosh', 'asin', 'asinh', 'atan', 'atan2', 'atanh', 'ceil', 'comb',
 'copysign', 'cos', 'cosh', 'degrees', 'dist', 'e', 'erf', 'erfc', 'exp',
 'expm1', 'fabs', 'factorial', 'floor', 'fmod', 'frexp', 'fsum', 'gamma', 
'gcd', 'hypot', 'inf', 'isclose', 'isfinite', 'isinf', 'isnan', 'isqrt',
 'ldexp', 'lgamma', 'log', 'log10', 'log1p', 'log2', 'modf', 'nan', 'perm', 
'pi', 'pow', 'prod', 'radians', 'remainder', 'sin', 'sinh', 'sqrt', 'tan',
 'tanh', 'tau', 'trunc']

Uses of dir() function

  • It is usually used for debugging purposes in simple day-to-day programs. The dir() function can list out all the attributes of that parameter passed,
  • dir() function is really useful when handling a lot of classes and functions, separately.
  • The dir() function can also list out all the available attributes for the module/list/dictionary. So it helps to know the new modules faster.
Pythonfunctions