Idioms and Anti-Idioms Question

[Lawrence D'Oliveiro]

In message <mailman.2018.1245772229.8015.python-list at python.org>, J. Cliff 
Dyer wrote:

> If the lines got separated, a leading + could disappear into its line
> without any errors showing up.  A trailing + would raise a syntax error.

Unless, of course, it was moved onto the previous line as part of whatever 
caused the separation of the lines. How would you guard against that?