needs tests/harness mem/mark
testbegin

\test unmark never do the opposite
\ There used to be a bug when the "inv" part of the "and"-ing was operated on
\ the wrong value
32 newmarklist const mymarks
1 mymarks marked? not #true
1 mymarks mark
1 mymarks marked? #true
mymarks markcnt 1 #eq
1 mymarks unmark
1 mymarks marked? not #true
mymarks markcnt 0 #eq
1 mymarks unmark \ this used to re-mark!
1 mymarks marked? not #true
mymarks markcnt 0 #eq

\test ?mark
3 mymarks ?mark not #true
3 mymarks ?mark #true
3 mymarks marked? #true
mymarks markcnt 1 #eq
3 mymarks unmark
mymarks markcnt 0 #eq

testend