1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
|
if not modules then modules = { } end modules ['node-ini'] = {
version = 1.001,
comment = "companion to node-ini.mkiv",
author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
copyright = "PRAGMA ADE / ConTeXt Development Team",
license = "see context related readme files"
}
--[[ldx--
<p>Most of the code that had accumulated here is now separated in
modules.</p>
--ldx]]--
-- this module is being reconstructed
local utf = unicode.utf8
local next, type = next, type
local format, concat, match, utfchar = string.format, table.concat, string.match, utf.char
local chardata = characters and characters.data
--[[ldx--
<p>We start with a registration system for atributes so that we can use the
symbolic names later on.</p>
--ldx]]--
attributes = attributes or { }
attributes.names = attributes.names or { }
attributes.numbers = attributes.numbers or { }
attributes.list = attributes.list or { }
attributes.unsetvalue = -0x7FFFFFFF
storage.register("attributes/names", attributes.names, "attributes.names")
storage.register("attributes/numbers", attributes.numbers, "attributes.numbers")
storage.register("attributes/list", attributes.list, "attributes.list")
local names, numbers, list = attributes.names, attributes.numbers, attributes.list
function attributes.define(name,number) -- at the tex end
if not numbers[name] then
numbers[name], names[number], list[number] = number, name, { }
end
end
--[[ldx--
<p>We can use the attributes in the range 127-255 (outside user space). These
are only used when no attribute is set at the \TEX\ end which normally
happens in <l n='context'/>.</p>
--ldx]]--
storage.shared.attributes_last_private = storage.shared.attributes_last_private or 127
function attributes.private(name) -- at the lua end (hidden from user)
local number = numbers[name]
if not number then
local last = storage.shared.attributes_last_private or 127
if last < 255 then
last = last + 1
storage.shared.attributes_last_private = last
end
number = last
numbers[name], names[number], list[number] = number, name, { }
end
return number
end
--[[ldx--
<p>Access to nodes is what gives <l n='luatex'/> its power. Here we
implement a few helper functions. These functions are rather optimized.</p>
--ldx]]--
--[[ldx--
<p>When manipulating node lists in <l n='context'/>, we will remove
nodes and insert new ones. While node access was implemented, we did
quite some experiments in order to find out if manipulating nodes
in <l n='lua'/> was feasible from the perspective of performance.</p>
<p>First of all, we noticed that the bottleneck is more with excessive
callbacks (some gets called very often) and the conversion from and to
<l n='tex'/>'s datastructures. However, at the <l n='lua'/> end, we
found that inserting and deleting nodes in a table could become a
bottleneck.</p>
<p>This resulted in two special situations in passing nodes back to
<l n='tex'/>: a table entry with value <type>false</type> is ignored,
and when instead of a table <type>true</type> is returned, the
original table is used.</p>
<p>Insertion is handled (at least in <l n='context'/> as follows. When
we need to insert a node at a certain position, we change the node at
that position by a dummy node, tagged <type>inline</type> which itself
has_attribute the original node and one or more new nodes. Before we pass
back the list we collapse the list. Of course collapsing could be built
into the <l n='tex'/> engine, but this is a not so natural extension.</p>
<p>When we collapse (something that we only do when really needed), we
also ignore the empty nodes. [This is obsolete!]</p>
--ldx]]--
nodes = nodes or { }
local hlist = node.id('hlist')
local vlist = node.id('vlist')
local glyph = node.id('glyph')
local glue = node.id('glue')
local penalty = node.id('penalty')
local kern = node.id('kern')
local whatsit = node.id('whatsit')
local traverse_id = node.traverse_id
local traverse = node.traverse
local free_node = node.free
local remove_node = node.remove
function nodes.remove(head, current, free_too)
local t = current
head, current = remove_node(head,current)
if t then
if free_too then
free_node(t)
t = nil
else
t.next, t.prev = nil, nil
end
end
return head, current, t
end
function nodes.delete(head,current)
return nodes.remove(head,current,true)
end
nodes.before = node.insert_before
nodes.after = node.insert_after
-- we need to test this, as it might be fixed now
function nodes.before(h,c,n)
if c then
if c == h then
n.next = h
n.prev = nil
h.prev = n
else
local cp = c.prev
n.next = c
n.prev = cp
if cp then
cp.next = n
end
c.prev = n
return h, n
end
end
return n, n
end
function nodes.after(h,c,n)
if c then
local cn = c.next
if cn then
n.next = cn
cn.prev = n
else
n.next = nil
end
c.next = n
n.prev = c
return h, n
end
return n, n
end
function nodes.replace(head,current,new)
if current and next then
local p, n = current.prev, current.next
new.prev, new.next = p, n
if p then
p.next = new
else
head = new
end
if n then
n.prev = new
end
free_node(current)
end
return head, current
end
-- will move
local function count(stack,flat)
local n = 0
while stack do
local id = stack.id
if not flat and id == hlist or id == vlist then
local list = stack.list
if list then
n = n + 1 + count(list) -- self counts too
else
n = n + 1
end
else
n = n + 1
end
stack = stack.next
end
return n
end
nodes.count = count
-- new
function attributes.ofnode(n)
local a = n.attr
if a then
local names = attributes.names
a = a.next
while a do
local number, value = a.number, a.value
texio.write_nl(format("%s : attribute %3i, value %4i, name %s",tostring(n),number,value,names[number] or '?'))
a = a.next
end
end
end
local left, space = lpeg.P("<"), lpeg.P(" ")
nodes.filterkey = left * (1-left)^0 * left * space^0 * lpeg.C((1-space)^0)
|