Pythonic way to print list items

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Pythonic way to print list items

I would like to know if there is a better way to print all objects in a Python list than this :

myList = [Person("Foo"), Person("Bar")]
print("n".join(map(str, myList)))

I read this way is not really good :

myList = [Person("Foo"), Person("Bar")]
for p in myList:

Isn’t there something like :

print(p) for p in myList

If not, my question is… why ? If we can do this kind of stuff with comprehensive lists, why not as a simple statement outside a list ?

Answer #1:

Assuming you are using Python 3.x:

print(*myList, sep='n')

You can get the same behavior on Python 2.x using from __future__ import print_function, as noted by mgilson in comments.

With the print statement on Python 2.x you will need iteration of some kind, regarding your question about print(p) for p in myList not working, you can just use the following which does the same thing and is still one line:

for p in myList: print p

For a solution that uses 'n'.join(), I prefer list comprehensions and generators over map() so I would probably use the following:

print 'n'.join(str(p) for p in myList)
Answered By: Andrew Clark

Answer #2:

I use this all the time :

l = [1,2,3,7]
print "".join([str(x) for x in l])
Answered By: lucasg

Answer #3:

[print(a) for a in list] will give a bunch of None types at the end though it prints out all the items

Answered By: ytpillai

Answer #4:

For Python 2.*:

If you overload the function __str__() for your Person class, you can omit the part with map(str, …). Another way for this is creating a function, just like you wrote:

def write_list(lst):
    for item in lst:
        print str(item)

There is in Python 3.* the argument sep for the print() function. Take a look at documentation.

Answered By: gukoff

Answer #5:

Expanding @lucasg’s answer (inspired by the comment it received):

To get a formatted list output, you can do something along these lines:

l = [1,2,5]
print ", ".join('%02d'%x for x in l)
01, 02, 05

Now the ", " provides the separator (only between items, not at the end) and the formatting string '02d'combined with %x gives a formatted string for each item x – in this case, formatted as an integer with two digits, left-filled with zeros.

Answered By: Floris

Answer #6:

To display each content, I use:

mylist = ['foo', 'bar']
indexval = 0
for i in range(len(mylist)):
    indexval += 1

Example of using in a function:

def showAll(listname, startat):
   indexval = startat
      for i in range(len(mylist)):
         indexval = indexval + 1
   except IndexError:
      print('That index value you gave is out of range.')

Hope I helped.

Answered By: ShinyMemes

Answer #7:

I think this is the most convenient if you just want to see the content in the list:

myList = ['foo', 'bar']
print('myList is %s' % str(myList))

Simple, easy to read and can be used together with format string.

Answered By: Rongzhao Zhang

Answer #8:

OP’s question is: does something like following exists, if not then why

print(p) for p in myList # doesn't work, OP's intuition

answer is, it does exist which is:

[p for p in myList] #works perfectly

Basically, use [] for list comprehension and get rid of print to avoiding printing None. To see why print prints None see this

Answered By: Gaurav Singhal

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