Chris Angelico writes:
Additionally, naming sub-parts of a large expression
can assist an
interactive debugger, providing useful display hooks and partial
results. Without a way to capture sub-expressions inline, this
would require refactoring of the original code; with assignment
expressions, this merely requires the insertion of a few
:= markers. Removing the need to refactor reduces the likelihood
that the code be inadvertently changed as part of debugging (a
common cause of Heisenbugs),
Period here preferred.
and is easier to dictate to a student or junior programmer.
True but gratuitous. It's also true that it's easier to dictate to Guido or Tim, though you might be happier if you let them refactor!