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, load = type, next, tostring, tonumber, load
local dump = string.dump
local formatters = string.formatters
local concat = table.concat
local scanners = tokens.scanners
local tokenbits = tokens.bits
local scanstring = scanners.string
local scanargument = scanners.argument
local scandelimited = scanners.delimited
local scanverbatim = scanners.verbatim
local scantokenlist = scanners.tokenlist
local scantoks = scanners.toks
local scaninteger = scanners.integer
local scancardinal = scanners.cardinal
local scannumber = scanners.number
local scanfloat = scanners.float
local scanposit = scanners.posit
local scankeyword = scanners.keyword
local scankeywordcs = scanners.keywordcs
local scanword = scanners.word
local scanletters = scanners.letters
local scankey = scanners.key
local scancode = scanners.code
local scanboolean = scanners.boolean
local scandimension = scanners.dimension
local scanglue = scanners.glue
local scangluevalues = scanners.gluevalues
local scangluespec = scanners.gluespec
local scancsname = scanners.csname
local scandetokened = scanners.detokened
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
local function scantable(t,data)
if not data then
data = { }
end
if t then
local wrapped = scanopen()
while true do
local key = scanword(true)
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
end
return data
end
function tokens.constant(s)
if type(s) == "string" then
return "'" .. s .. "'"
else
return s
end
end
scanners.list = scanlist
scanners.table = scantable
scanners.conditional = scanconditional
function scanners.whd()
local width, height, depth
while true do
if scankeyword("width") then
width = scandimension()
elseif scankeyword("height") then
height = scandimension()
elseif scankeyword("depth") then
depth = scandimension()
else
break
end
end
if width or height or depth then
return width or 0, height or 0, depth or 0
else
-- we inherit
end
end
local l = utf.byte("[")
local r = utf.byte("]")
local function scanbracketed()
local s = scandelimited(l, r)
if s then
return s
else
local readstate = status.getreadstate()
report_scan("missing argument in line %i of %a", readstate.linenumber, readstate.filename)
return ""
end
end
local function scanoptional()
return scandelimited(l, r) or ""
end
local function scanbracketedasis()
return scandelimited(l, r, false)
end
local function scanargumentasis()
return scanargument(false)
end
local function scancsnameunchecked()
return scancsname(true)
end
scanners.bracketed = scanbracketed
scanners.optional = scanoptional
scanners.bracketedasis = scanbracketedasis
scanners.argumentasis = scanargumentasis
scanners.csnameunchecked = scancsnameunchecked
local scanlua = function()
local s = load("return " .. scanstring())
if s then
return s()
end
end
scanners.lua = scanlua
--------.detokenize = function() return scanners.tokenstring(false) end -- needs testing
local shortcuts = {
tokens = tokens,
bits = tokenbits,
open = open,
close = close,
scanners = scanners,
scanstring = scanstring,
scanargument = scanargument,
scantokenstring = scanners.tokenstring,
-- scandetokenize = scanners.detokenize,
scanverbatim = scanverbatim,
scantokenlist = scantokenlist,
scantoks = scantoks,
scaninteger = scaninteger,
scancardinal = scancardinal,
scannumber = scannumber,
scanfloat = scanfloat,
scanposit = scanposit,
scantable = scantable, -- not directly useable
scankeyword = scankeyword,
scankeywordcs = scankeywordcs,
scanword = scanword,
scanletters = scanletters,
-- scankey = scankey,
scancode = scancode,
scanboolean = scanboolean,
scanglue = scanglue, -- list
scangluespec = scangluespec,
scangluevalues = scangluevalues,
scandimension = scandimension,
scanbox = scanners.box,
scanhbox = scanners.hbox,
scanvbox = scanners.vbox,
scanvtop = scanners.vtop,
scanconditional = scanconditional,
scanopen = scanopen,
scanclose = scanclose,
scanlist = scanlist,
scancsname = scancsname,
scancsnameunchecked = scancsnameunchecked,
scandelimited = scandelimited, -- not directly useable
scanbracketed = scanbracketed,
scanoptional = scanoptional,
scanbracketedasis = scanbracketedasis,
scanargumentasis = scanargumentasis,
scandetokened = scandetokened,
scanlua = scanlua,
todimen = todimen,
tonumber = tonumber,
tostring = tostring,
toboolean = toboolean,
inspect = inspect,
report = report_scan,
posit = posit,
-- obsolete:
scandimen = scandimension,
scanintegerargument = scanners.integerargument,
scandimensionargument = scanners.dimensionargument,
}
tokens.shortcuts = shortcuts
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",
}
-- We could just pickup a keyword but then we really need to make sure that no number
-- follows it when that is the assignment and adding an optional = defeats the gain
-- in speed. Currently we have sources with no spaces (\startcontextdefinitioncode
-- ...) so it fails there.
--
-- Another drawback is that we then need to use { } instead of ending with \relax (as
-- we can do now) but that is no big deal. It's just that I then need to check the TeX
-- end. More pain than gain and a bit risky too. Using scanletters works better, but
-- the gain is only some 10 percent but if we don't have keywords with numbers it might
-- make sense in the end, some day.
local f_if = formatters[ " if scankeywordcs('%s') then data['%s'] = scan%s()"]
local f_elseif = formatters[" elseif scankeywordcs('%s') then data['%s'] = scan%s()"]
----- f_if_x = formatters[ " if not data['%s'] and scankeywordcs('%s') then data['%s'] = scan%s()"]
----- f_elseif_x = formatters[" elseif not data['%s'] and scankeywordcs('%s') then data['%s'] = scan%s()"]
----- f_if = formatters[" local key = scanletters() if key == '' then break elseif key == '%s' then data['%s'] = scan%s()"]
----- f_elseif = formatters[" elseif key == '%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 scankeywordcs('%s') then data['%s'] = %s(scan%s())"]
local f_elseif_c = formatters[" elseif scankeywordcs('%s') then data['%s'] = %s(scan%s())"]
local f_scan_c = formatters["%s(scan%s())"]
-- see above
----- f_if_c = formatters[" local key = scanletters() if key == '' then break elseif key == '%s' then data['%s'] = %s(scan%s())"]
----- f_elseif_c = formatters[" elseif k == '%s' then data['%s'] = %s(scan%s())"]
local f_any = formatters[" else local key = scanword(true) if key then data[key] = scan%s() else break end end"]
local f_any_c = formatters[" else local key = scanword(true) if key then data[key] = %s(scan%s()) else break end end"]
local s_done <const> = " else break end"
local f_any_all = formatters[" local key = scanword(true) if key then data[key] = scan%s() else break end"]
local f_any_all_c = formatters[" local key = scanword(true) 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_singular = formatters["%\nt\n%\nt\n\nreturn function(%s)\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 = scanopen()
while true do
]] .. "%\nt\n" .. [[
%s
end
if wrapped then
scanclose()
end
]] ]
-- using these shortcuts saves temporary small tables (okay, it looks uglier)
local presets = {
["1 string" ] = { "string" },
["2 strings"] = { "string", "string" },
["3 strings"] = { "string", "string", "string" },
["4 strings"] = { "string", "string", "string", "string" },
["5 strings"] = { "string", "string", "string", "string", "string" },
["6 strings"] = { "string", "string", "string", "string", "string", "string" },
["7 strings"] = { "string", "string", "string", "string", "string", "string", "string" },
["8 strings"] = { "string", "string", "string", "string", "string", "string", "string", "string" },
["1 argument" ] = { "argument" },
["2 arguments"] = { "argument", "argument" },
["3 arguments"] = { "argument", "argument", "argument" },
["4 arguments"] = { "argument", "argument", "argument", "argument" },
["1 integer"] = { "integer" },
["2 integers"] = { "integer", "integer" },
["3 integers"] = { "integer", "integer", "integer" },
["4 integers"] = { "integer", "integer", "integer", "integer" },
["1 optional"] = { "optional" },
["2 optionals"] = { "optional", "optional" },
["3 optionals"] = { "optional", "optional", "optional" },
["4 optionals"] = { "optional", "optional", "optional", "optional" },
}
tokens.presets = presets
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 args
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)
-- r[m] = (m > 1 and f_elseif_x or f_if_x)(t1,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 p = t and presets[t] -- already done in implement
if p then
t = p
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)
n = n + 1
f[n] = 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)
n = n + 1
f[n] = 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)
n = n + 1
f[n] = f_action_s(i,i)
end
code = f_simple(f,code)
else
return scanners[ti]
end
elseif #t == 0 then
if specification.usage == "value" then
code = "b"
args = "_,b"
else
code = ""
args = ""
end
if a then
tokens._action = a
for i=1,#a do
code = f_action_f(i,code)
n = n + 1
f[n] = f_action_s(i,i)
end
end
code = f_singular(c,f,args,code)
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)
n = n + 1
f[n] = 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()