bug#61091: 30.0.50; y-or-n-p clobbers match data

[Richard Stallman]

[[[ To any NSA and FBI agents reading my email: please consider    ]]]
[[[ whether defending the US Constitution against all enemies,     ]]]
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  >   In general, Lisp programs should not rely on any
  > function not to clobber match data, unless that function is documented
  > to preserve match data.

Allowance should be made for the fact that `y-or-n-p'
was safe for the match data for over 35 years.

-- 
Dr Richard Stallman (https://stallman.org)
Chief GNUisance of the GNU Project (https://gnu.org)
Founder, Free Software Foundation (https://fsf.org)
Internet Hall-of-Famer (https://internethalloffame.org)