On Sunday, May 31, 2015 at 3:13:47 PM UTC+10, Alex Ames wrote:
>
> I lost multiple days attempting to pin down this behavior. I had something 
> along the lines of
> x = a + b
>      + c
> It's not clear to me why the second line is a valid expression. At the 
> very least, it would be nice for lint to catch these, or an optional `...` 
> line-continuation operator.
>

The + operator is a valid unary prefix operator, so +c is a perfectly 
reasonable expression, 
see 
http://julia.readthedocs.org/en/latest/manual/mathematical-operations/#arithmetic-operators.

Lint might want to warn about unused expressions, but that won't catch 
examples like the one Scott showed where the expression result is the 
function return.

Lint might also want to warn about effect free expressions like +c.

But that will still only find a small subset of this class of possible 
problems and will likely have a high false positive rate so it will be 
annoying.

The best is to simply develop the habit of breaking expressions *after* 
operators:

x = a + b +
          c

Cheers
Lex
 

>
> On Saturday, May 30, 2015 at 11:21:18 AM UTC-5, Gabriel Mihalache wrote:
>>
>> Once you spend a few days tracking down a bug due to this, you never 
>> forget. The idea would be to find a way to save people from this experience.
>>
>> Some lines are naturally long because e.g. the equation is long or 
>> because you prefer long, informative variable names. You can always use 
>> variables for parts of the expression but then that just feels like working 
>> around poor language features/design.
>>
>

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