U+27DE "⟞" Long Left Tack Unicode Character

U+27DE "⟞" Long Left Tack is a mathematical symbol used primarily in the field of logic and theoretical computer science to represent a specific type of relation or operator, often appearing in sequent calculus or as a variant of the turnstile notation. Unlike the standard turnstile, the "tack" shape with an extended horizontal line emphasizes a distinct semantic role, such as indicating a longer scope or separation in formal derivations. This character belongs to the "Miscellaneous Mathematical Symbols-A" block and is designed for use in typesetting complex logical expressions where precise visual distinction is required.