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authorPhilipp Gesang <phg42.2a@gmail.com>2013-09-14 03:50:48 -0700
committerPhilipp Gesang <phg42.2a@gmail.com>2013-09-14 03:50:48 -0700
commit65cee1110cb5a033891524176c26c9184f4cbfd9 (patch)
tree78609d37f58a625867b5e3ab4bded0a1c809e063 /luaotfload-auxiliary.lua
parent464577e5185aceac6428cba6585713eb3a233a0b (diff)
parentf1fefb2184a372ef7418807d1eeb4d9d159591a2 (diff)
downloadluaotfload-65cee1110cb5a033891524176c26c9184f4cbfd9.tar.gz
Merge pull request #134 from phi-gamma/master
[aux,characters] import further Context code
Diffstat (limited to 'luaotfload-auxiliary.lua')
-rw-r--r--luaotfload-auxiliary.lua125
1 files changed, 107 insertions, 18 deletions
diff --git a/luaotfload-auxiliary.lua b/luaotfload-auxiliary.lua
index da3f5f2..311fae9 100644
--- a/luaotfload-auxiliary.lua
+++ b/luaotfload-auxiliary.lua
@@ -368,35 +368,124 @@ aux.name_of_slot = name_of_slot
resides. The file is huge (>3.7 MB as of 2013) and not part of the
isolated font loader. Nevertheless, we include a partial version
generated by the mkcharacters script that contains only the
- “direction” and “mirror” fields of each character defined.
+ a subset of the fields of each character defined.
+
+ Currently, these are (compare the mkcharacters script!)
+
+ · "direction"
+ · "mirror"
+ · "category"
+ · "textclass"
+
+ The directional information is required for packages like Simurgh [0]
+ to work correctly. In an early stage [1] it was necessary to load
+ further files from Context directly, including the full blown version
+ of char-def. Since we have no use for most of the so imported
+ functionality, the required parts have been isolated and are now
+ instated along with luaotfload-characters.lua. We can extend the set
+ of imported features easily should it not be enough.
+
+ [0] https://github.com/persian-tex/simurgh
+ [1] http://tex.stackexchange.com/a/132301/14066
--doc]]--
-characters = characters or { } --- should be created in basics-gen
-characters.data = { }
-local chardef = "luaotfload-characters"
+characters = characters or { } --- should be created in basics-gen
+characters.data = nil
+local chardef = "luaotfload-characters"
do
- local chardata
- local index = function (t, k)
+ local setmetatableindex = function (t, f)
+ local mt = getmetatable (t)
+ if mt then
+ mt.__index = f
+ else
+ setmetatable (t, { __index = f })
+ end
+ end
+
+ --- there are some special tables for each field that provide access
+ --- to fields of the character table by means of a metatable
+
+ local mkcharspecial = function (characters, tablename, field)
+
+ local chardata = characters.data
+
+ if chardata then
+ local newspecial = { }
+ characters [tablename] = newspecial --> e.g. “characters.data.mirrors”
+
+ local idx = function (t, char)
+ local c = chardata [char]
+ if c then
+ local m = c [field] --> e.g. “mirror”
+ if m then
+ t [char] = m
+ return m
+ end
+ end
+ newspecial [char] = false
+ return char
+ end
+
+ setmetatableindex (newspecial, idx)
+ end
+
+ end
+
+ local mkcategories = function (characters) -- different from the others
+
+ local chardata = characters.data
+
+ setmetatable (characters, { __index = function (t, char)
+ if char then
+ local c = chardata [char]
+ c = c.category or char
+ t [char] = c
+ return c
+ end
+ end})
+
+ end
+
+ local load_failed = false
+ local chardata --> characters.data; loaded on demand
+
+ local load_chardef = function ()
+
+ log ("Loading character metadata from %s.", chardef)
+ chardata = dofile (kpse.find_file (chardef, "lua"))
+
if chardata == nil then
- log("Loading character metadata from %s.", chardef)
- chardata = dofile(kpse.find_file(chardef, "lua"))
- if chardata == nil then
- warning("Could not load %s; continuing with empty character table.",
+ warning ("Could not load %s; continuing \z
+ with empty character table.",
chardef)
- chardata = { }
- end
+ chardata = { }
+ load_failed = true
end
- return chardata[k]
+
+ characters = { } --- nuke metatable
+ characters.data = chardata
+
+ --- institute some of the functionality from char-ini.lua
+
+ mkcharspecial (characters, "mirrors", "mirror")
+ mkcharspecial (characters, "directions", "direction")
+ mkcharspecial (characters, "textclasses", "textclass")
+ mkcategories (characters)
+
end
- local mt = getmetatable(characters.data)
- if mt then
- mt.__index = index
- else
- setmetatable(characters.data, { __index = index })
+ local charindex = function (t, k)
+ if chardata == nil and load_failed ~= true then
+ load_chardef ()
+ end
+
+ return characters [k]
end
+
+ setmetatableindex (characters, charindex)
+
end
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