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# Following work by @jiahao, we compute character widths using a combination of#   * character category#   * UAX 11: East Asian Width#   * a few exceptions as needed# Adapted from http://nbviewer.ipython.org/gist/jiahao/07e8b08bf6d8671e9734## We used to also use data from GNU Unifont, but that has proven unreliable# and unlikely to match widths assumed by terminals.## Requires Julia (obviously) and FontForge. #############################################################################CharWidths = Dict{Int,Int}() ############################################################################## Use ../libutf8proc for category codes, rather than the one in Julia,# to minimize bootstrapping complexity when a new version of Unicode comes out.catcode(c) = ccall((:utf8proc_category,"../libutf8proc"), Cint, (Int32,), c) # utf8proc category constants (must match h)const UTF8PROC_CATEGORY_CN = 0const UTF8PROC_CATEGORY_LU = 1const UTF8PROC_CATEGORY_LL = 2const UTF8PROC_CATEGORY_LT = 3const UTF8PROC_CATEGORY_LM = 4const UTF8PROC_CATEGORY_LO = 5const UTF8PROC_CATEGORY_MN = 6const UTF8PROC_CATEGORY_MC = 7const UTF8PROC_CATEGORY_ME = 8const UTF8PROC_CATEGORY_ND = 9const UTF8PROC_CATEGORY_NL = 10const UTF8PROC_CATEGORY_NO = 11const UTF8PROC_CATEGORY_PC = 12const UTF8PROC_CATEGORY_PD = 13const UTF8PROC_CATEGORY_PS = 14const UTF8PROC_CATEGORY_PE = 15const UTF8PROC_CATEGORY_PI = 16const UTF8PROC_CATEGORY_PF = 17const UTF8PROC_CATEGORY_PO = 18const UTF8PROC_CATEGORY_SM = 19const UTF8PROC_CATEGORY_SC = 20const UTF8PROC_CATEGORY_SK = 21const UTF8PROC_CATEGORY_SO = 22const UTF8PROC_CATEGORY_ZS = 23const UTF8PROC_CATEGORY_ZL = 24const UTF8PROC_CATEGORY_ZP = 25const UTF8PROC_CATEGORY_CC = 26const UTF8PROC_CATEGORY_CF = 27const UTF8PROC_CATEGORY_CS = 28const UTF8PROC_CATEGORY_CO = 29 ############################################################################## Use a default width of 1 for all character categories that are# letter/symbol/number-like, as well as for unassigned/private-use chars.# This can be overriden by UAX 11# below, but provides a useful nonzero fallback for new codepoints when# a new Unicode version has been released but Unifont hasn't been updated yet. zerowidth = Set{Int}() # categories that may contain zero-width charspush!(zerowidth, UTF8PROC_CATEGORY_MN)push!(zerowidth, UTF8PROC_CATEGORY_MC)push!(zerowidth, UTF8PROC_CATEGORY_ME)push!(zerowidth, UTF8PROC_CATEGORY_SK)push!(zerowidth, UTF8PROC_CATEGORY_ZL)push!(zerowidth, UTF8PROC_CATEGORY_ZP)push!(zerowidth, UTF8PROC_CATEGORY_CC)push!(zerowidth, UTF8PROC_CATEGORY_CF)push!(zerowidth, UTF8PROC_CATEGORY_CS)for c in 0x0000:0x110000    if catcode(c) ∉ zerowidth        CharWidths[c] = 1    endend ############################################################################## Widths from UAX #11: East Asian Width#   .. these take precedence for all codepoints#      listed explicitly as wide/full/narrow/half-width for line in readlines(open("EastAsianWidth.txt"))    #Strip comments    (isempty(line) || line[1] == '#') && continue    precomment = split(line, '#')[1]    #Parse code point range and width code    tokens = split(precomment, ';')    length(tokens) >= 2 || continue    charrange = tokens[1]    width = strip(tokens[2])    #Parse code point range into Julia UnitRange    rangetokens = split(charrange, "..")    charstart = parse(UInt32, "0x"*rangetokens[1])    charend = parse(UInt32, "0x"*rangetokens[length(rangetokens)>1 ? 2 : 1])     #Assign widths    for c in charstart:charend        if width=="W" || width=="F" # wide or full            CharWidths[c]=2        elseif width=="Na"|| width=="H"            CharWidths[c]=1        end    endend ############################################################################## A few exceptions to the above cases, found by manual comparison# to other wcwidth functions and similar checks. for c in keys(CharWidths)    cat = catcode(c)     # make sure format control character (category Cf) have width 0    # (some of these, like U+0601, can have a width in some cases    #  but normally act like prepended combining marks.  U+fff9 etc    #  are also odd, but have zero width in typical terminal contexts)    if cat==UTF8PROC_CATEGORY_CF        CharWidths[c]=0    end     # Unifont has nonzero width for a number of non-spacing combining    # characters, e.g. (in 7.0.06): f84,17b4,17b5,180b,180d,2d7f, and    # the variation selectors    if cat==UTF8PROC_CATEGORY_MN        CharWidths[c]=0    end     # We also assign width of one to unassigned and private-use    # codepoints (Unifont includes ConScript Unicode Registry PUA fonts,    # but since these are nonstandard it seems questionable to use Unifont metrics;    # if they are printed as the replacement character U+FFFD they will have width 1).    if cat==UTF8PROC_CATEGORY_CO || cat==UTF8PROC_CATEGORY_CN        CharWidths[c]=1    end     # for some reason, Unifont has width-2 glyphs for ASCII control chars    if cat==UTF8PROC_CATEGORY_CC        CharWidths[c]=0    endend #Soft hyphen is typically printed as a hyphen (-) in terminals.CharWidths[0x00ad]=1 #By definition, should have zero width (on the same line)#0x002028 '
' category: Zl name: LINE SEPARATOR/#0x002029 '
' category: Zp name: PARAGRAPH SEPARATOR/CharWidths[0x2028]=0CharWidths[0x2029]=0 ############################################################################## Output (to a file or pipe) for processing by data_generator.rb,# encoded as a sequence of intervals. firstc = 0x000000lastv = 0uhex(c) = uppercase(string(c,base=16,pad=4))for c in 0x0000:0x110000    global firstc, lastv    v = get(CharWidths, c, 0)    if v != lastv || c == 0x110000        v < 4 || error("invalid charwidth $v for $c")        if firstc+1 < c            println(uhex(firstc), "..", uhex(c-1), "; ", lastv)        else            println(uhex(firstc), "; ", lastv)        end        firstc = c        lastv = v    endend