Summary of N ways of string concatenation in python

There are many string connection methods in python. I am writing code today. Let me summarize by the way:

The most original string connection method: str1 + str2
python’s new string connection syntax: str1, str2
Strange string methods: str1 str2
% Connection string: 'name:%s; sex: ' % ('tom', 'male')
String list connection: str.join(some_list)

The first type, presumably as long as you have programming Experienced people probably know that you can directly use "+" to connect two strings:

'Jim' + 'Green' = 'JimGreen'

The second one is more special, if the two strings use "comma" separated, then the two strings will be concatenated, but there will be an extra space between the strings:

'Jim', 'Green' = 'Jim Green'

The third one is also unique to python, Just put two strings together, with or without whitespace: the two strings are automatically concatenated into one string:

'Jim''Green' = 'JimGreen'
'Jim' 'Green' = 'JimGreen '

The fourth function is more powerful and draws on the function of the printf function in C language. If you have a foundation in C language, just read the documentation. This method uses the symbol "%" to connect a string and a group of variables. The special marks in the string will be automatically replaced with the variables in the variable group on the right:

'%s, %s' % ('Jim', 'Green') = 'Jim, Green'

The fifth technique is to use the string function join. This function accepts a list, and then uses a string to join each element in the list:

var_list = ['tom', 'david', 'john']
a = '###'
a.join(var_list) = 'tom###david###john'

In fact, there is another string connection method in python, but it is not used much, which is string multiplication, such as:

a = 'abc'
a * 3 = 'abcabcabc'