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-rw-r--r--tex/context/base/toks-scn.lua437
1 files changed, 437 insertions, 0 deletions
diff --git a/tex/context/base/toks-scn.lua b/tex/context/base/toks-scn.lua
new file mode 100644
index 000000000..84924c694
--- /dev/null
+++ b/tex/context/base/toks-scn.lua
@@ -0,0 +1,437 @@
+if not modules then modules = { } end modules ['toks-scn'] = {
+ version = 1.001,
+ author = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+ copyright = "PRAGMA ADE / ConTeXt Development Team",
+ license = "see context related readme files"
+}
+
+-- Writing this kind of code (and completing the newtoken code base) is fun. I did
+-- so with the brilliant film music from The Girl with the Dragon Tattoo running in a
+-- loop in the background (three cd's by Trent Reznor and Atticus Ross). An alien
+-- feeling helps with alien code.
+
+-- todo: more \let's at the tex end
+
+local type, next, tostring, tonumber = type, next, tostring, tonumber
+
+local formatters = string.formatters
+local concat = table.concat
+
+local scanners = tokens.scanners
+local tokenbits = tokens.bits
+
+local scanstring = scanners.string
+local scaninteger = scanners.integer
+local scannumber = scanners.number
+local scankeyword = scanners.keyword
+local scanword = scanners.word
+local scancode = scanners.code
+local scanboolean = scanners.boolean
+local scandimen = scanners.dimen
+
+local todimen = number.todimen
+local toboolean = toboolean
+
+local lpegmatch = lpeg.match
+local p_unquoted = lpeg.Cs(lpeg.patterns.unquoted)
+
+local trace_compile = false trackers.register("tokens.compile", function(v) trace_compile = v end)
+local report_compile = logs.reporter("tokens","compile")
+local report_scan = logs.reporter("tokens","scan")
+
+local open = tokenbits.open
+local close = tokenbits.close
+
+local function scanopen()
+ while true do
+ local c = scancode(open)
+ if c == 123 then
+ return true
+ -- elseif c ~= 32 then
+ elseif not c then
+ return
+ end
+ end
+end
+
+local function scanclose()
+ while true do
+ local c = scancode(close)
+ if c == 125 then
+ return true
+ -- elseif c ~= 32 then
+ elseif not c then
+ return
+ end
+ end
+end
+
+scanners.scanopen = scanopen
+scanners.scanclose = scanclose
+
+local function scanlist()
+ local wrapped = scanopen()
+ local list = { }
+ local size = 0
+ while true do
+ local entry = scanstring()
+ if entry then
+ size = size + 1
+ list[size] = entry
+ else
+ break
+ end
+ end
+ if wrapped then
+ scanclose()
+ end
+ return list
+end
+
+local function scanconditional()
+ local kw = scanword()
+ if kw == "true" then
+ return true
+ end
+ if kw == "false" then
+ return false
+ end
+ local c = scaninteger()
+ if c then
+ return c == 0 -- with a conditional 0=true
+ end
+ return nil
+end
+
+scanners.list = scanlist
+scanners.conditional = scanconditional
+
+local shortcuts = {
+ tokens = tokens,
+ bits = tokenbits,
+ open = open,
+ close = close,
+ scanners = scanners,
+ scanstring = scanstring,
+ scaninteger = scaninteger,
+ scannumber = scannumber,
+ scankeyword = scankeyword,
+ scanword = scanword,
+ scancode = scancode,
+ scanboolean = scanboolean,
+ scandimen = scandimen,
+ scandimension = scandimen,
+ scanconditional = scanconditional,
+ scanopen = scanopen,
+ scanclose = scanclose,
+ scanlist = scanlist,
+ todimen = todimen,
+ tonumber = tonumber,
+ tostring = tostring,
+ toboolean = toboolean,
+ inspect = inspect,
+ report = report_scan,
+}
+
+tokens.shortcuts = shortcuts
+
+local load = load
+local dump = string.dump
+
+local function loadstripped(code)
+ return load(code,nil,nil,shortcuts)
+ -- return load(dump(load(code),true),nil,nil,shortcuts)
+end
+
+tokens.converters = {
+ tonumber = "tonumber",
+ tostring = "tostring",
+ toboolean = "toboolean",
+ todimen = "todimen",
+ toglue = "todimen",
+}
+
+local f_if = formatters[ " if scankeyword('%s') then data['%s'] = scan%s()"]
+local f_elseif = formatters[" elseif scankeyword('%s') then data['%s'] = scan%s()"]
+local f_local = formatters["local scan%s = scanners.%s"]
+local f_scan = formatters["scan%s()"]
+local f_shortcut = formatters["local %s = scanners.converters.%s"]
+
+local f_if_c = formatters[ " if scankeyword('%s') then data['%s'] = %s(scan%s())"]
+local f_elseif_c = formatters[" elseif scankeyword('%s') then data['%s'] = %s(scan%s())"]
+local f_scan_c = formatters["%s(scan%s())"]
+
+local f_any = formatters[" else local key = scanword() if key then data[key] = scan%s() else break end end"]
+local f_any_c = formatters[" else local key = scanword() if key then data[key] = %s(scan%s()) else break end end"]
+local s_done = " else break end"
+
+local f_any_all = formatters[" local key = scanword() if key then data[key] = scan%s() else break end"]
+local f_any_all_c= formatters[" local key = scanword() if key then data[key] = %s(scan%s()) else break end"]
+
+local f_table = formatters["%\nt\nreturn function()\n local data = { }\n%s\n return %s\nend\n"]
+local f_sequence = formatters["%\nt\n%\nt\n%\nt\nreturn function()\n return %s\nend\n"]
+local f_simple = formatters["%\nt\nreturn function()\n return %s\nend\n"]
+local f_string = formatters["%q"]
+local f_action_f = formatters["action%s(%s)"]
+local f_action_s = formatters["local action%s = tokens._action[%s]"]
+local f_nested = formatters["local function scan%s()\n local data = { }\n%s\n return data\nend\n"]
+
+-- local f_check = formatters[ [[
+-- local wrapped = false
+-- while true do
+-- local c = scancode(open)
+-- if c == 123 then
+-- wrapped = true
+-- break
+-- elseif c ~= 32 then
+-- break
+-- end
+-- end
+-- while true do
+-- ]] .. "%\nt\n" .. [[
+-- %s
+-- end
+-- if wrapped then
+-- while true do
+-- local c = scancode(close)
+-- if c == 125 then
+-- break
+-- elseif c ~= 32 then
+-- break
+-- end
+-- end
+-- end
+-- ]] ]
+
+local f_check = formatters[ [[
+ local wrapped = scanopen()
+ while true do
+ ]] .. "%\nt\n" .. [[
+ %s
+ end
+ if wrapped then
+ scanclose()
+ end
+]] ]
+
+function tokens.compile(specification)
+ local f = { }
+ local n = 0
+ local c = { }
+ local t = specification.arguments or specification
+ local a = specification.actions or nil
+ if type(a) == "function" then
+ a = { a }
+ end
+ local code
+ local function compile(t,nested)
+ local done = s_done
+ local r = { }
+ local m = 0
+ for i=1,#t do
+ local ti = t[i]
+ if ti == "*" and i == 1 then
+ done = f_any_all("string")
+ else
+ local t1 = ti[1]
+ local t2 = ti[2] or "string"
+ if type(t2) == "table" then
+ n = n + 1
+ f[n] = compile(t2,n)
+ t2 = n
+ end
+ local t3 = ti[3]
+ if type(t3) == "function" then
+ -- todo: also create shortcut
+ elseif t3 then
+ c[t3] = f_shortcut(t3,t3)
+ if t1 == "*" then
+ if i == 1 then
+ done = f_any_all_c(t3,t2)
+ break
+ else
+ done = f_any_c(t3,t2)
+ end
+ else
+ m = m + 1
+ r[m] = (m > 1 and f_elseif_c or f_if_c)(t1,t1,t3,t2)
+ end
+ else
+ if t1 == "*" then
+ if i == 1 then
+ done = f_any_all(t2)
+ break
+ else
+ done = f_any(t2)
+ end
+ else
+ m = m + 1
+ r[m] = (m > 1 and f_elseif or f_if )(t1,t1,t2)
+ end
+ end
+ end
+ end
+ local c = f_check(r,done)
+ if nested then
+ return f_nested(nested,c)
+ else
+ return c
+ end
+ end
+ local tt = type(t)
+ if tt == "string" then
+ if a then
+ local s = lpegmatch(p_unquoted,t)
+ if s and t ~= s then
+ code = t
+ else
+ code = f_scan(t)
+ end
+ tokens._action = a
+ for i=1,#a do
+ code = f_action_f(i,code)
+ f[#f+1] = f_action_s(i,i)
+ end
+ code = f_simple(f,code)
+ else
+ return scanners[t]
+ end
+ elseif tt ~= "table" then
+ return
+ elseif #t == 1 then
+ local ti = t[1]
+ if type(ti) == "table" then
+ ti = compile(ti)
+ code = "data"
+ if a then
+ tokens._action = a
+ for i=1,#a do
+ code = f_action_f(i,code)
+ f[#f+1] = f_action_s(i,i)
+ end
+ end
+ code = f_table(f,ti,code)
+ elseif a then
+ code = f_scan(ti)
+ tokens._action = a
+ for i=1,#a do
+ code = f_action_f(i,code)
+ f[#f+1] = f_action_s(i,i)
+ end
+ code = f_simple(f,code)
+ else
+ return scanners[ti]
+ end
+ else
+ local r = { }
+ local p = { }
+ local m = 0
+ for i=1,#t do
+ local ti = t[i]
+ local tt = type(ti)
+ if tt == "table" then
+ if ti[1] == "_constant_" then
+ local v = ti[2]
+ if type(v) == "string" then
+ r[i] = f_string(v)
+ else
+ r[i] = tostring(v)
+ end
+ else
+ m = m + 1
+ p[m] = compile(ti,100+m)
+ r[i] = f_scan(100+m)
+ end
+ elseif tt == "number" then
+ r[i] = tostring(ti)
+ elseif tt == "boolean" then
+ r[i] = tostring(ti)
+ else
+ local s = lpegmatch(p_unquoted,ti)
+ if s and ti ~= s then
+ r[i] = ti -- a string, given as "'foo'" or '"foo"'
+ elseif scanners[ti] then
+ r[i] = f_scan(ti)
+ else
+ report_compile("unknown scanner %a",ti)
+ r[i] = ti
+ end
+ end
+ end
+ code = concat(r,",")
+ if a then
+ tokens._action = a
+ for i=1,#a do
+ code = f_action_f(i,code)
+ f[#f+1] = f_action_s(i,i)
+ end
+ end
+ code = f_sequence(c,f,p,code)
+ end
+ if not code then
+ return
+ end
+ if trace_compile then
+ report_compile("code: %s",code)
+ end
+ local code, message = loadstripped(code)
+ if code then
+ code = code() -- sets action
+ else
+ report_compile("error in code: %s",code)
+ report_compile("error message: %s",message)
+ end
+ if a then
+ tokens._action = nil
+ end
+ if code then
+ return code
+ end
+end
+
+-- local fetch = tokens.compile {
+-- "string",
+-- "string",
+-- {
+-- { "data", "string" },
+-- { "tab", "string" },
+-- { "method", "string" },
+-- { "foo", {
+-- { "method", "integer" },
+-- { "compact", "number" },
+-- { "nature" },
+-- { "*" }, -- any key
+-- } },
+-- { "compact", "string", "tonumber" },
+-- { "nature", "boolean" },
+-- { "escape", "string" },
+-- { "escape" },
+-- }
+-- "boolean",
+-- }
+--
+-- os.exit()
+
+function tokens.scantable(t,data)
+ if not data then
+ data = { }
+ end
+ local wrapped = scanopen()
+ while true do
+ local key = scanword()
+ if key then
+ local get = t[key]
+ if get then
+ data[key] = get()
+ else
+ -- catch all we can get
+ end
+ else
+ break
+ end
+ end
+ if wrapped then
+ scanclose()
+ end
+ return data
+end