added a library for retrieving documentation

lib/doc.lua

@@ -0,0 +1,113 @@
+local doc = {}
+doc.searchers = {}
+doc.tctab = {
+ ["string"] = 31,
+ ["table"] = 32,
+ ["number"] = 33,
+ ["boolean"] = 35,
+ ["function"] = 36
+}
+
+function doc.parsefile(path) -- string -- table -- parses file from *path* to return a documentation table
+ local fdoc = {}
+ local f = io.open(path)
+ local lines = {}
+ for l in f:read("*a"):gmatch("[^\n]+") do
+  if l:find("function") and not l:find("local") then
+   lines[#lines+1] = l
+  end
+ end
+ for k,v in pairs(lines) do
+  local name, args, desc = v:match("function%s+(.+)%s*%((.*)%)%s*%-%-%s*(.+)")
+  if name and args and desc then
+   local fd = {["description"]=desc or desc,["args"]={},["atypes"]={}}
+   for word in args:gmatch("[^%s,]+") do
+    fd.args[#fd.args+1] = {word}
+    fd.atypes[word] = "unknown"
+   end
+   local argtypes, outtypes, description = desc:match("(.-)%-%-(.-)%-%-%s*(.+)")
+   if argtypes and outtypes and description then
+    local wc = 1
+    for word in argtypes:gmatch("%S+") do
+     fd.args[wc][2] = word
+     fd.atypes[fd.args[wc][1]] = word
+     wc = wc + 1
+    end
+    local wc = 1
+    for word in outtypes:gmatch("%S+") do
+     fd.outtypes = fd.outtypes or {}
+     fd.outtypes[#fd.outtypes+1] = word
+    end
+    fd.description = description
+   end
+   fdoc[name] = fd
+  end
+ end
+ return fdoc
+end
+
+function doc.format(fdoc) -- table -- string -- returns VT100 formatted documentation from documentation table *fdoc*
+ local rs = "" -- string to return
+ for fname,finfo in pairs(fdoc) do
+  if rs:len() > 0 then rs = rs .. "\n\n" end
+  local as = "" -- string containing arguments for a given function, with colours for type
+  for k,v in ipairs(finfo.args) do
+   local c = doc.tctab[v[2]] or 0
+   if k > 1 then
+    as = as .. ", "
+   end
+   if v[2] then
+    as = string.format("%s%s: \27[%im%s\27[0m",as,v[2],c,v[1])
+   else
+    as = string.format("%s\27[%im%s\27[0m",as,c,v[1])
+   end
+  end
+  local rv = ""
+  if finfo.outtypes then
+   rv = ": "
+   for k,v in ipairs(finfo.outtypes) do
+    if k > 1 then
+     rv = rv .. ", "
+    end
+    local c = doc.tctab[v] or 0
+    rv = string.format("%s\27[%im%s\27[0m",rv,c,v)
+   end
+  end
+  local nd = finfo.description
+  for k,v in pairs(finfo.atypes) do
+   local c = doc.tctab[v] or 7
+   nd=nd:gsub("%*"..k.."%*","\27["..tostring(c).."m"..k.."\27[0m")
+  end
+  rs = string.format("%s\27[36m%s\27[0m(%s)%s\n%s",rs,fname,as,rv,nd)
+ end
+ return rs
+end
+
+function doc.searchers.lib(name) -- string -- string string -- Tries to find a documentation from a library with *name*. Returns either a string of documentation, or false and a reason.
+ local lib = os.getenv("LIB") or "/boot/lib"
+ local dt
+ for d in lib:gmatch("[^\n]+") do
+  if fs.exists(d.."/"..name) then
+   dt = doc.parsefile(d.."/"..name)
+  elseif fs.exists(d.."/"..name..".lua") then
+   dt = doc.parsefile(d.."/"..name..".lua")
+  end
+ end
+ if not dt then return false, "unable to find documentation for "..tostring(name) end
+ return doc.format(dt)
+end
+
+function doc.docs(topic) -- string -- boolean -- Displays the documentation for *topic*, returning true, or errors. Also callable as just doc().
+ local lib = os.getenv("LIB") or "/boot/lib"
+ local dt
+ for k,v in pairs(doc.searchers) do
+  dt=v(topic)
+  if dt then
+   print(dt)
+   return true
+  end
+ end
+ error("unable to find documentation for "..tostring(name))
+end
+
+return setmetatable(doc,{__call=function(_,topic) return doc.docs(topic) end})