chunk ::= {stat [';']} [laststat [';']]
block ::= chunk
stat ::= varlist1 '=' explist1 |
functioncall |
do block end |
while exp do block end |
            repeat block until exp |
           if exp then block {elseif exp then block} [else block] end |
            for Name '=' exp ',' exp [',' exp] do block end |
            for namelist in explist1 do block end |
            function funcname funcbody |
            local function Name funcbody |
            local namelist ['=' explist1]
     laststat ::= return [explist1] | break
   funcname ::= Name {'.' Name} [':' Name]
     varlist1 ::= var {',' var}
     var ::=  Name | prefixexp '[' exp ']' | prefixexp '.' Name
      namelist ::= Name {',' Name}
      explist1 ::= {exp ','} exp
      exp ::=  nil | false | true | Number | String | '...' | function |
            prefixexp | tableconstructor | exp binop exp | unop exp
      prefixexp ::= var | functioncall | '(' exp ')'
       functioncall ::=  prefixexp args | prefixexp ':' Name args
      args ::=  '(' [explist1] ')' | tableconstructor | String
      function ::= function funcbody
      funcbody ::= '(' [parlist1] ')' block end
    parlist1 ::= namelist [',' '...'] | '...'
      tableconstructor ::= '{' [fieldlist] '}'
      fieldlist ::= field {fieldsep field} [fieldsep]
      field ::= '[' exp ']' '=' exp | Name '=' exp | exp
      fieldsep ::= ',' | ';'
binop ::= '+' | '-' | '*' | '/' | '^' | '%' | '..' |
     '<' | '<=' | '>' | '>=' | '==' | '~=' |
     and | or
 unop ::= '-' | not | '#'