Error using the print function inside a lambda function in Python 2.7

Question

I'm running a simple code in Python 2.7, but it is giving me syntax error.

hello = lambda first: print("Hello", first)

The error reported is SyntaxError: invalid syntax.

print() is not a function in Python 2 unless you add from __future__ import print_function to the top of your script. Why are you trying to use it as a function? — Martijn Pieters
– Martijn Pieters, Commented Jul 25, 2015 at 18:55
@MartijnPieters The tutorial I was referring to was using the same. When I tried to mimic it, I got an error. I tried the same without the brackets like we normally do in python 2.7 but that failed too. — TheChetan
– TheChetan, Commented Jul 25, 2015 at 20:18
Your tutorial appears to be for Python 3; either switch tutorials or install Python 3, you'll have other problems. — Martijn Pieters
– Martijn Pieters, Commented Jul 25, 2015 at 22:24

vaultah · Accepted Answer · 2015-07-25 19:03:05Z

5

Python disallows the use of statements in lambda expressions:

Note that functions created with lambda expressions cannot contain statements or annotations.

print is a statement in Python 2, unless you import the print_function feature from __future__:

>>> lambda x: print(x)
  File "<stdin>", line 1
    lambda x: print(x)
                  ^
SyntaxError: invalid syntax
>>> from __future__ import print_function
>>> lambda x: print(x)
<function <lambda> at 0x7f2ed301d668>

edited Jul 25, 2015 at 19:03

answered Jul 25, 2015 at 18:56

vaultah

46.9k12 gold badges120 silver badges145 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

CMCDragonkai Over a year ago

Is there a way to use lambda x: print(x) then 1+1 inside a lamda, where the then represents something that just drops the None type and returns the right expression?

vaultah Over a year ago

@CMCDragonkai I honestly can't think of a reason why you might want to do this, but since print (the function) returns None, you can use the or operator: lambda x: print(x) or other_value.

Collectives™ on Stack Overflow

Error using the print function inside a lambda function in Python 2.7

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related