1 lua comment -- random code from http://lua-users.org/wiki/TextJustification
2 lua comment -- easy queue implementation ------------------------------------------
4 lua code function q_create()
11 lua code function q_insert(q, s)
12 lua code q[q.last] = s
13 lua code q.last = q.last + 1
16 lua code function q_empty(q)
17 lua code return q.first >= q.last
20 lua code function q_remove(q)
21 lua code if q_empty(q) then
24 lua code local s = q[q.first]
25 lua code q[q.first] = nil
26 lua code q.first = q.first+1
30 lua code function q_card(q)
31 lua code return q.last - q.first
34 lua code function q_length(q, f)
35 lua code local l, i = 0, q.first
36 lua code while i < q.last do
37 lua code l = l + strlen(q[i])
43 lua comment -- line creation routines ------------------------------------------
45 lua comment -- justifies one line to fit into MAX columns
46 lua code function justify(q)
47 lua code local blanks = MAX - q_length(q)
48 lua code local skips = q_card(q) - 1
49 lua code local line = q_remove(q)
50 lua code local quotient = floor(blanks/skips)
51 lua code local reminder = blanks/skips - quotient
52 lua code local error = 0
53 lua code while skips > 0 do
54 lua code error = error + reminder
55 lua code if error >= 0.5 then
56 lua code error = error - 1
57 lua code line = line .. strrep(" ", quotient+1)
59 lua code line = line .. strrep(" ", quotient)
61 lua code line = line .. q_remove(q)
62 lua code skips = skips - 1
64 lua code return line or ""
67 lua comment -- join all words with one space between them
68 lua code function catenate(q)
69 lua code local line = q_remove(q)
70 lua code while not q_empty(q) do
71 lua code line = line .. " " .. q_remove(q)
73 lua code return line or ""
76 lua comment -- main program -----------------------------------------------------
78 lua comment -- tries to get MAX from command-line
79 lua code if not arg or getn(arg) < 1 then
82 lua code MAX = tonumber(arg[1])
83 lua code if not MAX or MAX < 0 then
88 lua comment -- collects all text from stdin
89 lua code text = q_create()
90 lua code line = read()
91 lua code while line do
92 lua code _, n = gsub(line, "(%S+)", function (s) q_insert(%text, s) end)
93 lua code if n == 0 then
94 lua code q_insert(text, "\n")
96 lua code line = read()
99 lua comment -- justify paragraphs
100 lua code line = q_create()
101 lua code word = q_remove(text)
103 lua code while word do
104 lua code if word == "\n" then
105 lua code if not q_empty(line) then
106 lua code write(catenate(line), "\n\n")
111 lua code elseif size + strlen(word) > MAX then
112 lua code write(justify(line), "\n")
115 lua code if word ~= "\n" then
116 lua code q_insert(line, word)
117 lua code size = size + strlen(word) + 1
119 lua code word = q_remove(text)
121 lua code write(catenate(line), "\n")