[Python-ideas] Special-case 3.x 'print x' SyntaxError

[Terry Reedy]

On 9/15/2014 4:23 AM, Chris Angelico wrote:
> On Mon, Sep 15, 2014 at 6:12 PM, Terry Reedy <tjreedy at udel.edu> wrote:
>> One of the problems with new Python programmers using 3.x is that they first
>> read 'print x' in 2.x based material, try 'print x' in 3.x, get
>> "SyntaxError: invalid syntax" (note the uninformative redundant message),
>> and go "huh?" or worse.
>>
>> Would it be possible to add detect this particular error and print a more
>> useful message?  I am thinking of something of something like
>> SyntaxError: calling the 'print' function requires ()s, as in "print(x)"
>> or maybe
>> SyntaxError: did you mean "print(...)"?
>
> You mean like this?
>
> rosuav at dewey:~$ python3
> Python 3.4.1+ (default, Aug 18 2014, 12:06:51)
> [GCC 4.9.1] on linux
> Type "help", "copyright", "credits" or "license" for more information.
>>>> print "Hello?"
>    File "<stdin>", line 1
>      print "Hello?"
>                   ^
> SyntaxError: Missing parentheses in call to 'print'

Excellent!  Someone's time machine strikes again.

-- 
Terry Jan Reedy