pub const OP_UNDERCUT: u8 = 0x17;Expand description
An undercutting defeater: combined with DEFEATER_BIT it invalidates the
inference link p ⇒ Oq without asserting ¬Oq (vs a rebutting defeater — a
DEFEATER_BIT node with an O/P/F opcode — which asserts the contrary). The
fingerprint match is identical (the opcode byte is masked out); only the
classification in DefeatKind differs.