1ESC-B(1) General Commands Manual ESC-B(1) 2 3NNAAMMEE 4 eesscc--BB - the roff escape B sequence: validate numerical expression 5 6DDEESSCCRRIIPPTTIIOONN 7 empty: 0 8 digit: 1 9 no number: 0 10 trailing garbage: 0 11 trailing operator: 0 12 infix operator: 1 13 infix and trailing operator: 0 14 chain of operations: 1 15 trailing para: 0 16 unclosed para: 0 17 empty pair of parentheses: 0 18 parentheses containing number: 1 19 complex expression: 1 20 other delimiter: 1 21 no closing delimiter: 0 22 23OpenBSD July 4, 2017 OpenBSD 24