Mathematical Right White Square Bracket

Mathematical Right White Square Bracket at U+27E7 closes a hollow double-line square bracket used as a specialized mathematical delimiter. It is part of the Miscellaneous Mathematical Symbols-A block and functions like a right bracket whose outline is “white” or open rather than solid. Its main role is in formal mathematics and logic, where authors need bracket shapes that are visually distinct from ordinary parentheses, square brackets, and double brackets. It is commonly paired with the matching left form to enclose expressions, meanings, intervals, semantic values, or syntactic objects, as in notations that distinguish one kind of bracketing from another. In denotational semantics, type theory, and programming-language theory, similar white bracket pairs are often used for interpretation brackets, such as enclosing a term to mean “the semantic value of this expression.” The right bracket marks the end of that special enclosure. Outside technical writing, it is rarely used, and it should not be substituted for a normal closing square bracket unless the notation specifically calls for this delimiter.