@@ -67,6 +67,7 @@ module Text.Pandoc.Pretty (
6767 , parens
6868 , quotes
6969 , doubleQuotes
70+ , charWidth
7071 )
7172
7273where
@@ -461,3 +462,39 @@ quotes = inside (char '\'') (char '\'')
461462doubleQuotes :: Doc -> Doc
462463doubleQuotes = inside (char '"') (char '"')
463464
465+-- | Returns width of a character in a monospace font: 0 for a combining
466+-- character, 1 for a regular character, 2 for an East Asian wide character.
467+charWidth :: Char -> Int
468+charWidth c =
469+ case c of
470+ _ | c >= '\x300' && c <= '\x36e' -> 0 -- combining
471+ | c == '\x3000' -> 2 -- full
472+ | c >= '\xFF01' && c <= '\xFF60' -> 2
473+ | c >= '\xFFE0' && c <= '\xFFE6' -> 2
474+ | c >= '\x1100' && c <= '\x1159' -> 2 -- wide
475+ | c >= '\x115F' && c <= '\x115F' -> 2
476+ | c >= '\x2329' && c <= '\x232A' -> 2
477+ | c >= '\x2E80' && c <= '\x2E99' -> 2
478+ | c >= '\x2E9B' && c <= '\x2EF3' -> 2
479+ | c >= '\x2F00' && c <= '\x2FD5' -> 2
480+ | c >= '\x2FF0' && c <= '\x2FFB' -> 2
481+ | c >= '\x3001' && c <= '\x303E' -> 2
482+ | c >= '\x3041' && c <= '\x3096' -> 2
483+ | c >= '\x3099' && c <= '\x30FF' -> 2
484+ | c >= '\x3105' && c <= '\x312C' -> 2
485+ | c >= '\x3131' && c <= '\x318E' -> 2
486+ | c >= '\x3190' && c <= '\x31B7' -> 2
487+ | c >= '\x31F0' && c <= '\x321E' -> 2
488+ | c >= '\x3220' && c <= '\x3243' -> 2
489+ | c >= '\x3250' && c <= '\x327D' -> 2
490+ | c >= '\x327F' && c <= '\x32FE' -> 2
491+ | c >= '\x3300' && c <= '\x33FF' -> 2
492+ | c >= '\xA000' && c <= '\xA48C' -> 2
493+ | c >= '\xA490' && c <= '\xA4C6' -> 2
494+ | c >= '\xF900' && c <= '\xFA2D' -> 2
495+ | c >= '\xFA30' && c <= '\xFA6A' -> 2
496+ | c >= '\xFE30' && c <= '\xFE52' -> 2
497+ | c >= '\xFE54' && c <= '\xFE66' -> 2
498+ | c >= '\xFE68' && c <= '\xFE6B' -> 2
499+ | c >= '\x2F800' && c <= '\x2FA1D' -> 2
500+ | otherwise -> 1