Python | Exploring the syntax and usage of list() to create a list by collecting elements from an iterable or converting a string

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list()

Python is a popular programming language that offers a wide range of built-in functions to perform various tasks. One of the most commonly used built-in functions is "list()", which creates a new list object.

The "list()" function can be used to create a new list object from an existing iterable object such as a string, tuple, or another list. It takes an iterable object as its argument and returns a list containing the elements of the iterable object.

Syntax: The syntax for the "list()" function is as follows:

list(iterable)

where:

iterable: The iterable object which needs to be converted to a list.

Example 1:

my_string = "Hello World"

my_list = list(my_string)

print(my_list)

In this example, we have created a string "my_string" with the value "Hello World". We then use the "list()" function to convert the string into a list and assign it to the variable "my_list". We then print the value of "my_list". The output of this code will be:

Output:

['H', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd']

Example 2:

my_tuple = (1, 2, 3, 4, 5)

my_list = list(my_tuple)

print(my_list)

In this example, we have created a tuple "my_tuple" with the values 1, 2, 3, 4, and 5. We then use the "list()" function to convert the tuple into a list and assign it to the variable "my_list". We then print the value of "my_list". The output of this code will be:

Output:

[1, 2, 3, 4, 5]

Example 3:

my_list_1 = [1, 2, 3]

my_list_2 = [4, 5, 6]

my_list = list(my_list_1 + my_list_2)

print(my_list)

In this example, we have created two lists "my_list_1" and "my_list_2" with the values 1, 2, 3 and 4, 5, 6 respectively. We then concatenate both the lists using the "+" operator and pass the result to the "list()" function to create a new list "my_list". We then print the value of "my_list". The output of this code will be:

Output:

[1, 2, 3, 4, 5, 6]

Example 4:

my_string = "Hello World"

my_list = list(my_string)

my_list[0] = 'J'

print(my_list)

In this example, we have created a string "my_string" with the value "Hello World". We then use the "list()" function to convert the string into a list and assign it to the variable "my_list". We then update the first element of "my_list" to 'J'. We then print the value of "my_list". The output of this code will be:

Output:

['J', 'e', 'l', 'l', 'o', ' ', 'W', 'o', 'r', 'l', 'd']

In conclusion, the "list()" function is a very useful built-in function in Python that creates a new list object. It can be used to create a new list from an existing iterable object such as a string, tuple, or another list.