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path: root/src/parser_min.lua
blob: 8750cfdae2dab162c1f379103842fd543773ebb9 (plain)
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local a, b, d, e, c = "String", "errorinfo", "function", "cannot use '...' outside a vararg function", "SuffixedExp"
local f = {}
local g = require("lpeg")
local h

if include ~= nil then
	h = include("./scope.lua")
else
	h = dofile("../src/scope.lua")
end

g.locale(g)
local i, j, k = g.P, g.S, g.V
local l, m, n, o = g.C, g.Carg, g.Cb, g.Cc
local p, q, r, s, t = g.Cf, g.Cg, g.Cmt, g.Cp, g.Ct
local u, v, w = g.alpha, g.digit, g.alnum
local x = g.xdigit
local y = g.space
local z = h.lineno
local A, B = h.new_scope, h.end_scope
local C, D = h.new_function, h.end_function
local E, F = h.begin_loop, h.end_loop
local G = h.insideloop
local H = g.P("/*")
local I = g.P("*/")
local J = (1 - H) ^ 0
local K = (1 - I) ^ 0
local L = H * K * I

local function M(N, O, P)
	local Q, R = z(N.subject, O)
	local S = "%s:%d:%d: syntax error, %s"

	return string.format(S, N.filename, Q, R, P)
end

local function Q(R, S, T)
	return T.ffp or S, T
end

local function U()
	return r(m(1), Q) * (l(k("OneWord")) + o("EOF")) / function(T, V)
		T.unexpected = V

		return T
	end
end

local function V()
	return U() / function(T)
		local W = T.ffp or 1
		local P = "unexpected '%s', expecting %s"
		P = string.format(P, T.unexpected, T.expected)

		return nil, M(T, W, P)
	end
end

local function W()
	return V()
end

local function X(R, S, T, Y)
	if not T.ffp or T.ffp < S then
		T.ffp = S
		T.list = {}
		T.list[Y] = Y
		T.expected = "'" .. Y .. "'"
	elseif S == T.ffp then
	end

	return false
end

local function Z(aa)
	return r(m(1) * o(aa), X)
end

local function ba(ca)
	ca = string.gsub(ca, "\\a", "\a")
	ca = string.gsub(ca, "\\b", "\b")
	ca = string.gsub(ca, "\\f", "\f")
	ca = string.gsub(ca, "\\n", "\n")
	ca = string.gsub(ca, "\\r", "\r")
	ca = string.gsub(ca, "\\t", "\t")
	ca = string.gsub(ca, "\\v", "\v")
	ca = string.gsub(ca, "\\\n", "\n")
	ca = string.gsub(ca, "\\\r", "\n")
	ca = string.gsub(ca, "\\'", "'")
	ca = string.gsub(ca, [[\\"]], [["]])
	ca = string.gsub(ca, "\\\\", "\\")

	return ca
end

local function da(ea, aa)
	return ea * k("Skip") + Z(aa) * i(false)
end

local function fa(ca)
	return da(i(ca), ca)
end

local function ga(ca)
	return da(i(ca) * -k("idRest"), ca)
end

local function ha(ia, ea)
	return t(q(s(), "pos") * q(o(ia), "tag") * ea)
end

local function ja(ka, la)
	return {
		["tag"] = "Op",
		["pos"] = la.pos,
		[1] = ka,
		[2] = la
	}
end

local function ma(na, ka, oa)
	if not ka then
		return na
	elseif ka == "add" then
		orka"sub"
		orka"mul"
		orka"div"
		orka"idiv"
		orka"mod"
		orka"pow"
		orka"concat"
		orka"band"
		orka"bor"
		orka"bxor"
		orka"shl"
		orka"shr"
		orka"eq"
		orka"lt"
		orka"le"
		orka"and"
		orka"or"
	elseif ka == "ne" then
	elseif ka == "gt" then
	elseif ka == "ge" then
	end
end

local function pa(ea, qa, ra)
	return p(ea * q(qa * ea) ^ 0, ma) + ra
end

local function sa(ea, qa)
	return p(ea * q(qa * ea) ^ 0, ma)
end

local function ta(ea, qa, ia)
	return ha(ia, (ea * (qa * ea) ^ 0) ^ (-1))
end

local function ua(ea, qa, ia)
	return ha(ia, ea * (qa * ea) ^ 0)
end

local va = {
	k("Lua"),
	["Lua"] = k("Shebang") ^ (-1) * k("Skip") * k("Chunk") * -1 + W(),
	["Chunk"] = k("Block"),
	["StatList"] = (fa(";") + k("Stat")) ^ 0,
	["Var"] = k("Id"),
	["Id"] = ha("Id", da(k("Name"), "Name")),
	["FunctionDef"] = ga(d) * k("FuncBody"),
	["FieldSep"] = fa(",") + fa(";"),
	["Field"] = ha("Pair", (fa("[") * k("Expr") * fa("]") * fa("=") * k("Expr")) + (ha(a, da(k("Name"), "Name")) * fa("=") * k("Expr"))) + k("Expr"),
	["FieldList"] = (k("Field") * (k("FieldSep") * k("Field")) ^ 0 * k("FieldSep") ^ (-1)) ^ (-1),
	["Constructor"] = ha("Table", fa("{") * k("FieldList") * fa("}")),
	["NameList"] = ua(k("Id"), fa(","), "NameList"),
	["ExpList"] = ua(k("Expr"), fa(","), "ExpList"),
	["FuncArgs"] = fa("(") * (k("Expr") * (fa(",") * k("Expr")) ^ 0) ^ (-1) * fa(")") + k("Constructor") + ha(a, da(k(a), a)),
	["Expr"] = k("SubExpr_1"),
	["SubExpr_1"] = sa(k("SubExpr_2"), k("OrOp")),
	["SubExpr_2"] = sa(k("SubExpr_3"), k("AndOp")),
	["SubExpr_3"] = sa(k("SubExpr_4"), k("RelOp")),
	["SubExpr_4"] = sa(k("SubExpr_5"), k("BOrOp")),
	["SubExpr_5"] = sa(k("SubExpr_6"), k("BXorOp")),
	["SubExpr_6"] = sa(k("SubExpr_7"), k("BAndOp")),
	["SubExpr_7"] = sa(k("SubExpr_8"), k("ShiftOp")),
	["SubExpr_8"] = k("SubExpr_9") * k("ConOp") * k("SubExpr_8") / ma + k("SubExpr_9"),
	["SubExpr_9"] = sa(k("SubExpr_10"), k("AddOp")),
	["SubExpr_10"] = sa(k("SubExpr_11"), k("MulOp")),
	["SubExpr_11"] = k("UnOp") * k("SubExpr_11") / ja + k("SubExpr_12"),
	["SubExpr_12"] = k("SimpleExp") * (k("PowOp") * k("SubExpr_11")) ^ (-1) / ma,
	["SimpleExp"] = ha("Number", da(k("Number"), "Number")) + ha(a, da(k(a), a)) + ha("Nil", ga("nil")) + ha("False", ga("false")) + ha("True", ga("true")) + ha("Dots", fa("...")) + k("FunctionDef") + k("Constructor") + k(c),
	[c] = p(k("PrimaryExp") * (ha("DotIndex", fa(".") * ha(a, da(k("Name"), "Name"))) + ha("ArrayIndex", fa("[") * k("Expr") * fa("]")) + ha("Invoke", q(fa(":") * ha(a, da(k("Name"), "Name")) * k("FuncArgs"))) + ha("Call", k("FuncArgs"))) ^ 0, function(wa, xa)
		if xa then
			if xa.tag == "Call" then
				orxa.tag"Invoke"

				local T = {
					["tag"] = xa.tag,
					["pos"] = wa.pos,
					[1] = wa
				}

				for ya, za in ipairs(xa) do
					table.insert(T, za)
				end

				return T
			else
				return {
					["tag"] = "Index",
					["pos"] = wa.pos,
					[1] = wa,
					[2] = xa[1]
				}
			end
		end

		return wa
	end),
	["PrimaryExp"] = k("Var") + ha("Paren", fa("(") * k("Expr") * fa(")")),
	["Block"] = ha("Block", k("StatList") * k("RetStat") ^ (-1)),
	["IfStat"] = ha("If", ga("if") * k("Expr") * ga("then") * k("Block") * (ga("elseif") * k("Expr") * ga("then") * k("Block")) ^ 0 * (ga("else") * k("Block")) ^ (-1) * ga("end")),
	["WhileStat"] = ha("While", ga("while") * k("Expr") * ga("do") * k("Block") * ga("end")),
	["DoStat"] = ga("do") * k("Block") * ga("end") / function(T)
		T.tag = "Do"

		return T
	end,
	["ForBody"] = ga("do") * k("Block"),
		["ForNum"] = ha("Fornum", k("Id") * fa("=") * k("Expr") * fa(",") * k("Expr") * (fa(",") * k("Expr")) ^ (-1) * k("ForBody")),
		["ForGen"] = ha("Forin", k("NameList") * ga("in") * k("ExpList") * k("ForBody")),
		["ForStat"] = ga("for") * (k("ForNum") + k("ForGen")) * ga("end"),
		["RepeatStat"] = ha("Repeat", ga("repeat") * k("Block") * ga("until") * k("Expr")),
			["FuncName"] = p(k("Id") * (fa(".") * ha(a, da(k("Name"), "Name"))) ^ 0, function(wa, xa)
				if xa then
					return {
						["tag"] = "Index",
						["pos"] = wa.pos,
						[1] = wa,
						[2] = xa
					}
				end

				return wa
			end) * (fa(":") * ha(a, da(k("Name"), "Name"))) ^ (-1) / function(wa, xa)
				if xa then
					return {
						["tag"] = "Index",
						["pos"] = wa.pos,
						["is_method"] = true,
						[1] = wa,
						[2] = xa
					}
				end

				return wa
			end,
			["ParList"] = k("NameList") * (fa(",") * fa("...") * ha("Dots", s())) ^ (-1) / function(T, ya)
				if ya then
					table.insert(T, ya)
				end

				return T
			end + fa("...") * ha("Dots", s()) / function(ya) return {ya} end + i(true) / function() return {} end,
			["FuncBody"] = ha("Function", fa("(") * k("ParList") * fa(")") * k("Block") * ga("end")),
			["FuncStat"] = ha("Set", ga(d) * k("FuncName") * k("FuncBody")) / function(T)
				if T[1].is_method then
					table.insert(T[2][1], 1, {
						["tag"] = "Id",
						[1] = "self"
					})
				end

				T[1] = {T[1]}
				T[2] = {T[2]}

				return T
			end,
			["LocalFunc"] = ha("Localrec", ga(d) * k("Id") * k("FuncBody")) / function(T)
				T[1] = {T[1]}
				T[2] = {T[2]}

				return T
			end,
			["LocalAssign"] = ha("Local", k("NameList") * ((fa("=") * k("ExpList")) + t(o()))),
			["LocalStat"] = ga("local") * (k("LocalFunc") + k("LocalAssign")),
			["LabelStat"] = ha("Label", fa("::") * da(k("Name"), "Name") * fa("::")),
			["BreakStat"] = ha("Break", ga("break")),
			["ContinueStat"] = ha("Continue", ga("continue")),
			["GoToStat"] = ha("Goto", ga("goto") * da(k("Name"), "Name")),
			["RetStat"] = ha("Return", ga("return") * (k("Expr") * (fa(",") * k("Expr")) ^ 0) ^ (-1) * fa(";") ^ (-1)),
			["ExprStat"] = r((k(c) * (o(function()
				local za = {...}
				local Aa = za[#za]
				table.remove(za)

				for Ba, ya in ipairs(za) do
					if ya.tag == "Id" then
						orya.tag"Index"
					else
						za[Ba] = ya

						return false
					end
				end

				za.tag = "VarList"
				za.pos = za[1].pos

				return true, {
					["tag"] = "Set",
					["pos"] = za.pos,
					[1] = za,
					[2] = Aa
				}
			end) * k("Assignment"))) + (k(c) * (o(function(R)
				if R.tag == "Call" then
					orR.tag"Invoke"
				else
					return true, R
				end

				return false
			end))), function(R, S, za, Aa, ...) return Aa(za, ...) end),
			["Assignment"] = ((fa(",") * k(c)) ^ 1) ^ (-1) * fa("=") * k("ExpList"),
			["Stat"] = k("IfStat") + k("WhileStat") + k("DoStat") + k("ForStat") + k("RepeatStat") + k("FuncStat") + k("LocalStat") + k("LabelStat") + k("BreakStat") + k("GoToStat") + k("ExprStat") + k("ContinueStat"),
			["Space"] = y ^ 1,
			["Equals"] = i("=") ^ 0,
			["Open"] = "[" * q(k("Equals"), "init") * "[" * i("\n") ^ (-1),
			["Close"] = "]" * l(k("Equals")) * "]",
			["CloseEQ"] = r(k("Close") * n("init"), function(R, S, ra, Ba) return ra == Ba end),
			["LongString"] = k("Open") * l((i(1) - k("CloseEQ")) ^ 0) * k("Close") / function(R, Ca) return R end,
			["Comment"] = i("--") * k("LongString") / function() return end + i("--") * (i(1) - i("\n")) ^ 0 + i("//") * (i(1) - i("\n")) ^ 0 + l(L) / function() return end,
			["Skip"] = (k("Space") + k("Comment")) ^ 0,
			["idStart"] = u + i("_"),
			["idRest"] = w + i("_"),
			["Keywords"] = i("and") + "break" + "do" + "elseif" + "else" + "end" + "false" + "for" + d + "goto" + "if" + "in" + "local" + "nil" + "not" + "or" + "repeat" + "return" + "then" + "true" + "until" + "while" + "continue",
				["Reserved"] = k("Keywords") * -k("idRest"),
				["Identifier"] = k("idStart") * k("idRest") ^ 0,
				["Name"] = -k("Reserved") * l(k("Identifier")) * -k("idRest"),
				["Hex"] = (i("0x") + i("0X")) * x ^ 1,
				["Expo"] = j("eE") * j("+-") ^ (-1) * v ^ 1,
				["Float"] = (((v ^ 1 * i(".") * v ^ 0) + (i(".") * v ^ 1)) * k("Expo") ^ (-1)) + (v ^ 1 * k("Expo")),
				["Int"] = v ^ 1,
				["Number"] = l(k("Hex") + k("Float") + k("Int")) / function(Y) return tonumber(Y) end,
				["ShortString"] = i([["]]) * l(((i("\\") * i(1)) + (i(1) - i([["]]))) ^ 0) * i([["]]) + i("'") * l(((i("\\") * i(1)) + (i(1) - i("'"))) ^ 0) * i("'"),
				[a] = k("LongString") + (k("ShortString") / function(R) return R end),
				["OrOp"] = ga("or") / "or" + fa("||") / "or",
				["AndOp"] = ga("and") / "and" + fa("&&") / "and",
				["RelOp"] = fa("~=") / "ne" + fa("==") / "eq" + fa("<=") / "le" + fa(">=") / "ge" + fa("<") / "lt" + fa(">") / "gt" + fa("!=") / "ne",
				["BOrOp"] = fa("|") / "bor",
				["BXorOp"] = fa("~") / "bxor",
				["BAndOp"] = fa("&") / "band",
				["ShiftOp"] = fa("<<") / "shl" + fa(">>") / "shr",
				["ConOp"] = fa("..") / "concat",
				["AddOp"] = fa("+") / "add" + fa("-") / "sub",
				["MulOp"] = fa("*") / "mul" + fa("/") / "div" + fa("%") / "mod",
				["UnOp"] = ga("not") / "not" + fa("-") / "unm" + fa("#") / "len" + fa("~") / "bnot" + fa("!") / "not",
				["PowOp"] = fa("^") / "pow",
				["Shebang"] = i("#") * (i(1) - i("\n")) ^ 0 * i("\n"),
				["OneWord"] = k("Name") + k("Number") + k(a) + k("Reserved") + i("...") + i(1)
			}

			local function Da(Ea, h, Fa)
				local Ga = Fa[1]
				forR = h

				do
					if Ea[R].label[Ga] then return true end
				end

				return false
			end

			local function Ga(Ea, Ha, O)
				local h = Ea.scope
				local Ia = Ea[h].label[Ha]

				if not Ia then
					Ea[h].label[Ha] = {
						["name"] = Ha,
						["pos"] = O
					}

					return true
				else
					local P = "label '%s' already defined at line %d"
					local Ja = z(Ea.errorinfo.subject, Ia.pos)
					P = string.format(P, Ha, Ja)

					return nil, M(Ea.errorinfo, O, P)
				end
			end

			local function Ia(Ea, Fa)
				local h = Ea.scope
				table.insert(Ea[h].goto, Fa)

				return true
			end

			local function Ja(Ea)
				forR = Ea.maxscope

				do
					for Ka, ya in ipairs(Ea[R].goto) do
						if not Da(Ea, R, ya) then
							local P = "no visible label '%s' for <goto>"
							P = string.format(P, ya[1])

							return nil, M(Ea.errorinfo, ya.pos, P)
						end
					end
				end

				return true
			end

			local function Ka(Ea, La)
				Ea.Ea.fscope.is_vararg = La
			end

			local Ma, Na, Oa
			local Pa, Qa, Ra, Sa

			Sa = function(Ea, Ta)
				local Ua = #Ta
				local La = false

				if 0 < Ua and Ta[Ua].tag == "Dots" then
					La = true
				end

				Ka(Ea, La)

				return true
			end

			local function Ua(Ea, Va)
				C(Ea)
				A(Ea)
				local Wa, P = Sa(Ea, Va[1])
				if not Wa then return Wa, P end
				Wa, P, Wa, P = Pa(Ea, Va[2])
				if not Wa then return Wa, P end
				B(Ea)
				D(Ea)

				return true
			end

			local function Wa(Ea, Va)
				local Xa, P = Na(Ea, Va[2])
				if not Xa then return Xa, P end

				if Va[3] then
					Xa, P, Xa, P = Na(Ea, Va[3])
					if not Xa then return Xa, P end
				end

				return true
			end

			local function Xa(Ea, Va)
				local Ya, P = Na(Ea, Va[1])
				if not Ya then return Ya, P end

				return true
			end

			local function Ya(Ea, Za)
				for ab, ya in ipairs(Za) do
					local ia = ya.tag

					if ia == "Pair" then
						local bb, P = Na(Ea, ya[1])
						if not bb then return bb, P end
						bb, P, bb, P = Na(Ea, ya[2])
						if not bb then return bb, P end
					else
						local bb, P = Na(Ea, ya)
						if not bb then return bb, P end
					end
				end

				return true
			end

			local function ab(Ea, Va)
				if not Ea.Ea.fscope.is_vararg then
					local P = e

					return nil, M(Ea.errorinfo, Va.pos, P)
				end

				return true
			end

			local function bb(Ea, cb)
				local db, P = Na(Ea, cb[1])
				if not db then return db, P end
				forS = 2

				do
					db, P, db, P = Na(Ea, cb[S])
					if not db then return db, P end
				end

				return true
			end

			local function db(Ea, eb)
				local fb, P = Na(Ea, eb[1])
				if not fb then return fb, P end
				forS = 3

				do
					fb, P, fb, P = Na(Ea, eb[S])
					if not fb then return fb, P end
				end

				return true
			end

			local function fb(Ea, Fa)
				local gb, P = Ra(Ea, Fa[1])
				if not gb then return gb, P end
				gb, P, gb, P = Qa(Ea, Fa[2])
				if not gb then return gb, P end

				return true
			end

			local function gb(Ea, Fa)
				if not G(Ea) then
					local P = "<break> not inside a loop"

					return nil, M(Ea.errorinfo, Fa.pos, P)
				end

				return true
			end

			local function hb(Ea, Fa)
				if not G(Ea) then
					local P = "<continue> not inside a loop"

					return nil, M(Ea.errorinfo, Fa.pos, P)
				end

				return true
			end

			local function ib(Ea, Fa)
				E(Ea)
				A(Ea)
				local jb, P = Qa(Ea, Fa[2])
				if not jb then return jb, P end
				jb, P, jb, P = Pa(Ea, Fa[3])
				if not jb then return jb, P end
				B(Ea)
				F(Ea)

				return true
			end

			local function jb(Ea, Fa)
				local kb, P
				E(Ea)
				A(Ea)
				kb, P, kb, P = Na(Ea, Fa[2])
				if not kb then return kb, P end
				kb, P, kb, P = Na(Ea, Fa[3])
				if not kb then return kb, P end

				if Fa[5] then
					kb, P, kb, P = Na(Ea, Fa[4])
					if not kb then return kb, P end
					kb, P, kb, P = Pa(Ea, Fa[5])
					if not kb then return kb, P end
				else
					kb, P, kb, P = Pa(Ea, Fa[4])
					if not kb then return kb, P end
				end

				B(Ea)
				F(Ea)

				return true
			end

			local function kb(Ea, Fa)
				local lb, P = Ia(Ea, Fa)
				if not lb then return lb, P end

				return true
			end

			local function lb(Ea, Fa)
				local mb = #Fa

				if mb % 2 == 0 then
					forS = 1

					do
						local nb, P = Na(Ea, Fa[S])
						if not nb then return nb, P end
						nb, P, nb, P = Pa(Ea, Fa[S + 1])
						if not nb then return nb, P end
					end
				else
					forS = 1

					do
						local nb, P = Na(Ea, Fa[S])
						if not nb then return nb, P end
						nb, P, nb, P = Pa(Ea, Fa[S + 1])
						if not nb then return nb, P end
					end

					local nb, P = Pa(Ea, Fa[mb])
					if not nb then return nb, P end
				end

				return true
			end

			local function mb(Ea, Fa)
				local nb, P = Ga(Ea, Fa[1], Fa.pos)
				if not nb then return nb, P end

				return true
			end

			local function nb(Ea, Fa)
				local ob, P = Qa(Ea, Fa[2])
				if not ob then return ob, P end

				return true
			end

			local function ob(Ea, Fa)
				local pb, P = Na(Ea, Fa[2][1])
				if not pb then return pb, P end

				return true
			end

			local function pb(Ea, Fa)
				E(Ea)
				local qb, P = Pa(Ea, Fa[1])
				if not qb then return qb, P end
				qb, P, qb, P = Na(Ea, Fa[2])
				if not qb then return qb, P end
				F(Ea)

				return true
			end

			local function qb(Ea, Fa)
				local rb, P = Qa(Ea, Fa)
				if not rb then return rb, P end

				return true
			end

			local function rb(Ea, Fa)
				E(Ea)
				local sb, P = Na(Ea, Fa[1])
				if not sb then return sb, P end
				sb, P, sb, P = Pa(Ea, Fa[2])
				if not sb then return sb, P end
				F(Ea)

				return true
			end

			Oa = function(Ea, sb)
				local ia = sb.tag

				if ia == "Id" then
					return true
				elseif ia == "Index" then
					thenelse"expecting a variable, but got a "
					ia()
				end
			end

			Ra = function(Ea, tb)
				for ub, ya in ipairs(tb) do
					local vb, P = Oa(Ea, ya)
					if not vb then return vb, P end
				end

				return true
			end

			Na = function(Ea, Va)
				local ia = Va.tag

				if ia == "Nil" then
					oria"True"
					oria"False"
					oria"Number"
					oria"someString"

					return true
				elseif ia == "Dots" then
				elseif ia == "Function" then
				elseif ia == "Table" then
				elseif ia == "Op" then
				elseif ia == "Paren" then
				elseif ia == "Call" then
				elseif ia == "Invoke" then
				elseif ia == "Id" then
					oria"Index"
					thenelse"expecting an expression, but got a "
					ia()
				end
			end

			Qa = function(Ea, ub)
				for vb, ya in ipairs(ub) do
					local wb, P = Na(Ea, ya)
					if not wb then return wb, P end
				end

				return true
			end

			Ma = function(Ea, Fa)
				local ia = Fa.tag

				if ia == "Do" then
					return Pa(Ea, Fa)
				elseif ia == "Set" then
				elseif ia == "While" then
				elseif ia == "Repeat" then
				elseif ia == "If" then
				elseif ia == "Fornum" then
				elseif ia == "Forin" then
				elseif ia == "Local" then
				elseif ia == "Localrec" then
				elseif ia == "Goto" then
				elseif ia == "Label" then
				elseif ia == "Return" then
				elseif ia == "Break" then
				elseif ia == "Continue" then
				elseif ia == "Call" then
				elseif ia == "Invoke" then
					thenelse"expecting a statement, but got a "
					ia()
				end
			end

			Pa = function(Ea, vb)
				local wb = {}
				A(Ea)

				for xb, ya in ipairs(vb) do
					local yb, P = Ma(Ea, ya)
					if not yb then return yb, P end
				end

				B(Ea)

				return true
			end

			local function wb(xb, N)
				assert(type(xb) == "table")
				assert(type(N) == "table")

				local Ea = {
					[b] = N,
					[d] = {}
				}

				C(Ea)
				Ka(Ea, true)
				local yb, P = Pa(Ea, xb)
				if not yb then return yb, P end
				D(Ea)
				yb, P, yb, P = Ja(Ea)
				if not yb then return yb, P end

				return xb
			end

			f.parse = function(yb, zb)
				local N = {
					["subject"] = yb,
					["filename"] = zb
				}

				g.setmaxstack(1000)
				local xb, Ab = g.match(va, yb, nil, N)
				if not xb then return xb, Ab end

				return wb(xb, N)
			end

			return f