diff -r 3abf90751a8f -r b86082df0bc0 tools/erlparse.lua --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/tools/erlparse.lua Sat Nov 29 23:59:27 2008 +0500 @@ -0,0 +1,130 @@ + +local file = nil; +local last = nil; +local function read(expected) + local ch; + if last then + ch = last; last = nil; + else ch = file:read(1); end + if expected and ch ~= expected then error("expected: "..expected.."; got: "..(ch or "nil")); end + return ch; +end +local function pushback(ch) + if last then error(); end + last = ch; +end +local function peek() + if not last then last = read(); end + return last; +end + +local _A, _a, _Z, _z, _0, _9, __, _space = string.byte("AaZz09_ ", 1, 8); +local function isAlpha(ch) + ch = string.byte(ch) or 0; + return (ch >= _A and ch <= _Z) or (ch >= _a and ch <= _z); +end +local function isNumeric(ch) + ch = string.byte(ch) or 0; + return (ch >= _0 and ch <= _9); +end +local function isVar(ch) + ch = string.byte(ch) or 0; + return (ch >= _A and ch <= _Z) or (ch >= _a and ch <= _z) or (ch >= _0 and ch <= _9) or ch == __; +end +local function isSpace(ch) + ch = string.byte(ch) or "x"; + return ch <= _space; +end + +local function readString() + read("\""); -- skip quote + local slash = nil; + local str = ""; + while true do + local ch = read(); + if ch == "\"" and not slash then break; end + str = str..ch; + end + str = str:gsub("\\.", {["\\b"]="\b", ["\\d"]="\d", ["\\e"]="\e", ["\\f"]="\f", ["\\n"]="\n", ["\\r"]="\r", ["\\s"]="\s", ["\\t"]="\t", ["\\v"]="\v", ["\\\""]="\"", ["\\'"]="'", ["\\\\"]="\\"}); + return str; +end +local function readSpecialString() + read("<"); read("<"); -- read << + local str = ""; + if peek() == "\"" then + local str = readString(); + elseif peek() ~= ">" then + error(); + end + read(">"); read(">"); -- read >> + return str; +end +local function readVar() + local var = read(); + while isVar(peek()) do + var = var..read(); + end + return var; +end +local function readNumber() + local num = read(); + while isNumeric(peek()) do + num = num..read(); + end + return tonumber(num); +end +local readItem = nil; +local function readTuple() + local t = {}; + read(); -- read { or [ + while true do + local item = readItem(); + if not item then break; end + table.insert(t, item); + end + read(); -- read } or ] + return t; +end +readItem = function() + local ch = peek(); + if ch == nil then return nil end + if ch == "{" or ch == "[" then + return readTuple(); + elseif isAlpha(ch) then + return readVar(); + elseif isNumeric(ch) then + return readNumber(); + elseif ch == "\"" then + return readString(); + elseif ch == "<" then + return readSpecialString(); + elseif isSpace(ch) or ch == "," then + read(); + return readItem(); + else + --print("Unknown char: "..ch); + return nil; + end +end +local function readChunk() + local x = readItem(); + if x then read("."); end + return x; +end +local function readFile(filename) + file = io.open(filename); + if not file then error("File not found: "..filename); os.exit(0); end + return function() + local x = readChunk(); + if not x and peek() then error("Invalid char: "..peek()); end + return x; + end; +end + +module "erlparse" + +function parseFile(file) + return readFile(file); +end + +return _M;