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help for use print in REPL - jip31 - Apr-29-2021

Hi
I try to test this basic code in REPL

a = [1, 2, 3, 4, 5]
for x in range(len(a)):
    print a[x]
I don't succeed to display the list result : 1, 2,3
After for x in range(len(a)): there is an identation
So I am doing tab + print(a) but there is an stdin error
what is wrong please?

RE: help for use print in REPL - DPaul - Apr-29-2021

Hi,

Perhaps you mean
print(x).
or
for x in a:
print(x)

Paul

RE: help for use print in REPL - jip31 - Apr-29-2021

(Apr-29-2021, 09:18 AM)DPaul Wrote: Hi,

Perhaps you mean
print(x).
or
for x in a:
print(x)

Paul

Hi
No
Like explained, I need to display the list and the name list is a

RE: help for use print in REPL - perfringo - Apr-29-2021

No, no and no. Never write such a code. This ain’t Java, this is Python:

for item in iterable:
    print(item)
And if you are using Python2 then support of it has ended quite some time ago. Consider upgrading.

RE: help for use print in REPL - ibreeden - Apr-29-2021

Hi Jip31,
Although it is right what Perfringo said, for the purpose of studying: what your code gives me is the following:
Error:
  File "forum03.py", line 3
    print a[x]
          ^
SyntaxError: Missing parentheses in call to 'print'. Did you mean print(a[x])?
print a[x] is old Python 2 syntax. In Python 3 "print()" is a function. When you correct this:
a = [1, 2, 3, 4, 5]
for x in range(len(a)):
    print(a[x])
... the result is:
Output:
1
2
3
4
5


RE: help for use print in REPL - jip31 - Apr-29-2021

(Apr-29-2021, 10:45 AM)ibreeden Wrote: Hi Jip31,
Although it is right what Perfringo said, for the purpose of studying: what your code gives me is the following:
Error:
  File "forum03.py", line 3
    print a[x]
          ^
SyntaxError: Missing parentheses in call to 'print'. Did you mean print(a[x])?
print a[x] is old Python 2 syntax. In Python 3 "print()" is a function. When you correct this:
a = [1, 2, 3, 4, 5]
for x in range(len(a)):
    print(a[x])
... the result is:
Output:
1
2
3
4
5


thanks ibredeen (sorry I have one week python background....)

RE: help for use print in REPL - jefsummers - Apr-29-2021

And a tip - whenever you have range(len(... there is a better way.
In this case
a = [1, 2, 3, 4, 5]
for x in a:
    print(x)
Reiterating Perfringo, but specifically this case. For x in a pulls the elements of the list a. You then print (using Python 3 syntax for the print statement)

You may also want to look at list comprehensions. Not the best example, but
a = [1,2,3,4,5]
[print(x) for x in a]
Gets it down to 2 lines

RE: help for use print in REPL - deanhystad - Apr-29-2021

I think it is poor practice using a comprehension or any code for its side effects. My linter agrees.

RE: help for use print in REPL - bernardand - Apr-30-2021

No, no and no. Never write such a code. This ain’t Java, this is Python

RE: help for use print in REPL - ndc85430 - Apr-30-2021

Really, people should be learning how to program more declaratively anyway (a good talk on this: https://youtu.be/nrVIlhtoE3Y). To be fair to Java, that's done by making use of the Streams API