19

How can I write multi-line code in the python REPL? :

aircraftdeMacBook-Pro:~ ldl$ python
Python 2.7.10 (default, Jul 30 2016, 19:40:32) 
[GCC 4.2.1 Compatible Apple LLVM 8.0.0 (clang-800.0.34)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

such as a sample example:

i = 0

while i < 10:
    i += 1
    print i

In the terminal I don't know hot to line feed in the python shell:

I tested the Control+Enter, and Shift+Enter, and Command+Enter, they all wrong:

>>> while i < 10:
... print i 
  File "<stdin>", line 2
    print i 
        ^
IndentationError: expected an indented block
aircraft
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6 Answers6

16

You can add a trailing backslash. For example, if I want to print a 1:

>>> print 1
1
>>> print \
... 1
1
>>>

If you write a \, Python will prompt you with ... (continuation lines) to enter code in the next line, so to say.

To resolve IndentationError: expected an indented block, put the next line after while loop in an indented block (press Tab key).

So, the following works:

>>> i=0
>>> while i < 10:
...   i+=1
...   print i
... 
1
2
3
4
5
6
7
8
9
10
Wasi Ahmad
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  • The indent also works as expected when the syntax is correct. – OneCricketeer Jun 20 '17 at 04:29
  • This one worked for me. I needed a solution working just in the command line, and not copy/pasting from a text editor. – DaReal May 26 '20 at 08:25
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    It only works up to one extra line. In the second line, if I press Enter or Shift+Enter, I get a syntax error. Indentation or not, makes no difference. – Unknow0059 Oct 16 '20 at 04:17
4

There comes out:

IndentationError: expected an indented block

So, when use the while loop, the next line should have the indented block(press Tab key).

>>> i = 0
>>> while i < 10:
...     i += 1
...     print i 
... 
1
2
3
4
5
6
7
8
9
10
>>>
aircraft
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2

Just copy the code and past it in the terminal, and press return. This code works perfect if you do that:

   i = 0 
..  
.. while i < 10: 
..     i += 1 
..     print(i)  
..   

1
2
3
4
5
6
7
8
9
10
developer_hatch
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2

Utilize the python3 - <<'EOF' command.

For instance:

python3 - <<'EOF'
a=7
b=5
print(a+b)
EOF

12

RobC
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anshul singh
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0

Python automatically detects code blocks in sections like for-next, while, etc. Just put a ':' <-- Colon symbol after some code.

Then the next line will have a continuation symbol ('...') in front of it instead of the prompt ('>>>')

Remember to press a tab to indent the code that you want to execute in the block. That will indent the line and tell Python that the code that follows is a part of the block.

Cyril Gupta
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0

Different approaches for the same problem.

This solution might be complex, but working my

one line of script can

`

$
$ test_var=$(python3 -c $"import yaml,sys; yaml_as_dict=(lambda :yaml.safe_load(open(f'{sys.argv[1]}','r').read()))()[sys.argv[2]][sys.argv[3]]; print(yaml_as_dict)" <argv1> <argv2> <argv3>)
$
$ echo $test_var
$

How to execute multiline python code from a bash script?

How can I put multiple statements in one line?

P_M
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