From 754983b9ff12abf4fd16b7f7a2d2bf7e0b024f0c Mon Sep 17 00:00:00 2001
From: Matthijs Kooijman <matthijs@stdin.nl>
Date: Sun, 6 Dec 2009 16:55:28 +0100
Subject: [PATCH] Add strikethrough to the lambda prettyprinter.

---
 Outline      |  1 -
 pret-lam.lua | 64 +++++++++++++++++++++++++++++++++-------------------
 2 files changed, 41 insertions(+), 24 deletions(-)

diff --git a/Outline b/Outline
index d08c12b..997276d 100644
--- a/Outline
+++ b/Outline
@@ -64,5 +64,4 @@ TODO: Reorder future work.
 TODO: Future work: Use Cλash
 TODO: Abstract
 TODO: Preface
-TODO: strikethrough in pret-lam
 TOOD: Footnote font has not lambda
diff --git a/pret-lam.lua b/pret-lam.lua
index 3cc01af..f8ddb67 100644
--- a/pret-lam.lua
+++ b/pret-lam.lua
@@ -49,6 +49,15 @@ local bases = {}
 -- Store the last line for each indent level
 local indentlines = {}
 
+function array_concat(a1, a2)
+    local res = a1
+    for k,v in ipairs(a2) do
+        table.insert(res, v)
+    end
+    return res
+end
+
+
 -- See if str starts with a symbol, and return the remaining string and that
 -- symbol. If no symbol from the table is matched, just returns the first
 -- character.  We can do a lookup directly, since symbols can be different in
@@ -212,38 +221,47 @@ vis.begin_of_inline = vis.begin_of_display
 vis.end_of_inline = vis.end_of_display
 
 function vis.flush_line(str,nested)
-    local result, state = { }, 0
-    local finish, change = buffers.finish_state, buffers.change_state
+    buffers.flush_result(vis.do_line(str), nested)   
+end
+
+function vis.do_line(str)
+    result = {}
     str = do_indent(str)
-    -- Set the colorscheme, which is used by finish_state and change_state
-    buffers.currentcolors = colors
     while str ~= "" do
         local found = false
         local word, symbol
-        -- See if the next token is a word
-        word, str = take_word(str)
-        if word then
-            if keywords[res] then
-                -- Make all keywords bold
-                word = "{\\bold " .. word ..  "}"
-                if keywords[res].small then
-                    word = "\\small" .. word -- Curlies were added above
+        local text, rest = utf.match(str, "^%-%-(.-)%-%-(.*)")
+        if text then
+            table.insert(result, '\\strikethrough{')
+            -- Recursively call ourselves to handle spaces gracefully.
+            result = array_concat(result, vis.do_line(text))
+            table.insert(result, '}')
+            -- Eat the processed characters
+            str = rest
+        else
+            -- See if the next token is a word
+            word, str = take_word(str)
+            if word then
+                if keywords[res] then
+                    -- Make all keywords bold
+                    word = "{\\bold " .. word ..  "}"
+                    if keywords[res].small then
+                        word = "\\small" .. word -- Curlies were added above
+                    end
+                else
+                    -- Process any subscripts in the word
+                    word = do_subscripts(word)
                 end
+                table.insert(result, word)
             else
-                -- Process any subscripts in the word
-                word = do_subscripts(word)
+                -- The next token is not a word, it must be a symbol
+                symbol, str = take_symbol(str)
+                table.insert(result, symbol)
             end
-        else
-            -- The next token is not a word, it must be a symbol
-            symbol, str = take_symbol(str)
         end
-
-        -- Append the resulting token
-        result[#result+1] = word or symbol
     end
-    
-    state = finish(state, result)
-    buffers.flush_result(result,nested)
+
+    return result
 end
 
 -- vim: set sw=4 sts=4 expandtab ai:
-- 
2.30.2