1 -- filename : type-trans.lua
2 -- comment : Pretty printing of core transformations. Parses a specific
3 -- syntax, consisting of a before / after with a dashed lined in
4 -- between, and some extra conditions to the right of the line.
5 -- Recreates this layout using frames and line commands.
6 -- author : Matthijs Kooijman, Universiteit Twente, NL
7 -- copyright: Matthijs Kooijman
10 local utf = unicode.utf8
12 vis = buffers.newvisualizer("trans")
15 -- A command to create a horizontal rule.
16 commands.rule = "\\blackrule[height=0.5pt,depth=0pt,width=.45\\textwidth]"
17 -- Pretty printer to use for the stuff before and after the line
18 commands.before_pret = "lam"
19 commands.after_pret = "lam"
20 -- Frame commands to use for the left (before + line + after) and right
21 -- (conditions) parts. Should include an opening {, which will be closed
23 commands.leftframe = "\\framed[offset=0mm,location=middle,strut=no,align=right,frame=off,width=.5\\textwidth]{\\sans"
24 commands.rightframe = "\\framed[offset=0mm,location=middle,strut=no,align=right,frame=off,width=.5\\textwidth]{"
26 -- A table to keep the lines in this buffer, so we can process them all at
30 -- Some helper functions
31 local function ltrim(s)
32 return (string.gsub(s, "^%s*", ""))
35 local function rtrim(s)
36 return (string.gsub(s, "%s*$", ""))
39 -- Insert n blank lines
40 local function blanks(n)
42 buffers.visualizers.handlers.default.empty_line()
46 -- Prettyprint the given lines using the given pretty printer
47 local function prettyprint(ppr, lines)
48 -- Change the current visualizer
49 buffers.setvisualizer('lam')
52 buffers.hooks.begin_of_display()
55 _, line = buffers.typeline(lines[i], i, #lines, line)
57 buffers.hooks.end_of_display()
59 -- Change the visualizer back
60 buffers.setvisualizer('trans')
63 -- Capture all lines, without generating any output
64 function vis.begin_of_display()
67 function vis.begin_of_line(n)
68 -- Don't generate output here
70 function vis.flush_line(str, nested)
71 table.insert(lines, str)
72 -- Don't generate output here
74 function vis.end_of_line(n)
75 -- Don't generate output here
77 function vis.empty_line()
78 table.insert(lines, '')
79 -- Don't generate output here
82 -- We do the actual work here. Process all the lines in the buffer and
83 -- generate output for them.
84 function vis.end_of_display()
85 -- Find the horizontal rule, and see how long it is.
88 match = utf.match(lines[i], "^%-%-%-*")
96 error("No horizontal separator found in:\n" .. table.concat(lines, "\n"))
99 -- Split the input in three parts. Stuff before the line, stuff
100 -- after the line, stuff to the right of the line.
101 before, after, rights = {}, {}, {}
105 -- Split the line into a left and right part
106 left = rtrim(utf.sub(line, 1, len))
107 right = ltrim(utf.sub(line, len + 1))
108 if utf.match(left, "^%-%-%-*") then
111 if utf.len(left) > 0 then
112 if not found_line then
113 table.insert(before, left)
115 table.insert(after, left)
119 if utf.len(right) > 0 then
120 table.insert(rights, right)
125 -- Real output starts here
128 -- Ensure the left and right frames end up next to each other.
129 tex.sprint("\\dontleavehmode")
131 -- Open and fill the left frame
132 tex.sprint(commands.leftframe)
134 prettyprint('lam', before)
136 tex.sprint(commands.rule)
138 prettyprint('lam', after)
140 -- Close the left frame
143 -- Open and fill the right frame
144 tex.sprint(commands.rightframe)
146 -- Insert spacer blank lines to align the middle condition with the
148 n_blanks = #before - math.ceil((#rights - 1) / 2)
149 n_blanks = math.max(0, n_blanks)
152 -- Print the conditions
154 tex.sprint(rights[i])
155 buffers.visualizers.handlers.default.end_of_line()
158 -- Fill up the remaining space with blanks
159 n_blanks = (#before + 1 + #after) - (n_blanks + #rights)
160 n_blanks = math.max(0, n_blanks)
163 -- Close the right frame
170 -- vim: set sw=4 sts=4 expandtab ai: