Custom metadata for top-level '(a <- foo(x))' being used to induce printing

[MichaelChirico]

Have seen a few hits on implicit_assignment_linter() like:

(a <- foo(x))

Here, the lint message can mention explicitly using print() for readability rather than this shorthand.

We should of course be careful not to mix this case which is similar on the parse tree:

AA && (BB <- foo(x))

[AshesITR]

Agreed. Linting only a top-level parenthesis means the XPath should start with / instead of //.