diff options
Diffstat (limited to 'tex/context/base/mkiv/l-unicode.lua')
| -rw-r--r-- | tex/context/base/mkiv/l-unicode.lua | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/tex/context/base/mkiv/l-unicode.lua b/tex/context/base/mkiv/l-unicode.lua index 3dec80013..b913d0cfc 100644 --- a/tex/context/base/mkiv/l-unicode.lua +++ b/tex/context/base/mkiv/l-unicode.lua @@ -1270,3 +1270,35 @@ function utf.chrlen(u) -- u is number (u < 0xFC and 5) or (u < 0xFE and 6) or 0 end + +-- hashing saves a little but not that much in practice +-- +-- local utf32 = table.setmetatableindex(function(t,k) local v = toutf32(k) t[k] = v return v end) + +local extract = bit32.extract +local char = string.char + +function unicode.toutf32string(n) + if n <= 0xFF then + return + char(n) .. + "\000\000\000" + elseif n <= 0xFFFF then + return + char(extract(n, 0,8)) .. + char(extract(n, 8,8)) .. + "\000\000" + elseif n <= 0xFFFFFF then + return + char(extract(n, 0,8)) .. + char(extract(n, 8,8)) .. + char(extract(n,16,8)) .. + "\000" + else + return + char(extract(n, 0,8)) .. + char(extract(n, 8,8)) .. + char(extract(n,16,8)) .. + char(extract(n,24,8)) + end +end |