9 – Полный синтаксис Lua
Ниже приведён полный синтаксис Lua в расширенной форме Бэкуса — Наура (extended BNF). Как обычно в расширенной BNF, {A} означает ноль или более A, а [A] означает необязательное A. (О приоритетах операторов см. §3.4.8; описание терминалов Name, Numeral и LiteralString см. в §3.1.)
chunk ::= block
block ::= {stat} [retstat]
stat ::= ‘;’ |
varlist ‘=’ explist |
functioncall |
label |
break |
goto Name |
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 explist do block end |
function funcname funcbody |
local function Name funcbody |
global function Name funcbody |
local attnamelist [‘=’ explist] |
global attnamelist [‘=’ explist] |
global [attrib] ‘*’
attnamelist ::= [attrib] Name [attrib] {‘,’ Name [attrib]}
attrib ::= ‘<’ Name ‘>’
retstat ::= return [explist] [‘;’]
label ::= ‘::’ Name ‘::’
funcname ::= Name {‘.’ Name} [‘:’ Name]
varlist ::= var {‘,’ var}
var ::= Name | prefixexp ‘[’ exp ‘]’ | prefixexp ‘.’ Name
namelist ::= Name {‘,’ Name}
explist ::= exp {‘,’ exp}
exp ::= nil | false | true | Numeral | LiteralString | ‘...’ | functiondef |
prefixexp | tableconstructor | exp binop exp | unop exp
prefixexp ::= var | functioncall | ‘(’ exp ‘)’
functioncall ::= prefixexp args | prefixexp ‘:’ Name args
args ::= ‘(’ [explist] ‘)’ | tableconstructor | LiteralString
functiondef ::= function funcbody
funcbody ::= ‘(’ [parlist] ‘)’ block end
parlist ::= namelist [‘,’ varargparam] | varargparam
varargparam ::= ‘...’ [Name]
tableconstructor ::= ‘{’ [fieldlist] ‘}’
fieldlist ::= field {fieldsep field} [fieldsep]
field ::= ‘[’ exp ‘]’ ‘=’ exp | Name ‘=’ exp | exp
fieldsep ::= ‘,’ | ‘;’
binop ::= ‘+’ | ‘-’ | ‘*’ | ‘/’ | ‘//’ | ‘^’ | ‘%’ |
‘&’ | ‘~’ | ‘|’ | ‘>>’ | ‘<<’ | ‘..’ |
‘<’ | ‘<=’ | ‘>’ | ‘>=’ | ‘==’ | ‘~=’ |
and | or
unop ::= ‘-’ | not | ‘#’ | ‘~’