top_level ->
    | element
    | value

element -> Name single_line_fields element_body:?

element_body -> "{" element_fields "}"

element_fields -> (_ element_field (__linebreak__ element_field):*):? __linebreak__

element_field ->
    | element
    | specifier_chain
    | element_property
    | value

element_property -> Name _ ("=" | ":") _ value

single_line_fields ->
    (first_single_line_field
        (__sl__ single_line_field):*):? _sl_

first_single_line_field ->
    | specifier_chain
    | __sl__ single_line_element_property
    | __sl__ single_line_value

single_line_field ->
    | specifier_chain
    | single_line_element_property
    | single_line_value

single_line_element_property ->
    Name _sl_ ("=" | ":") _sl_ value

single_line_value ->
    | array
    | Int
    | Float
    | String
    | bool
    | Null

specifier_chain -> specifier:+

specifier ->
    | Id
    | Class

value ->
    | object
    | array
    | Int
    | Float
    | String
    | bool
    | Null

object -> "{" object_properties "}"

object_properties ->
    (_ object_property (_ "," _ object_property):* _ ",":?):? _

object_property -> (Name | String) _ ("=" | ":") _ value

array -> "[" array_values "]"

array_values -> (_ value (_ "," _ value):* _ ",":?):? _

bool -> True | False

__linebreak__ -> mandatory_linebreak
__sl__ -> mandatory_single_line_whitespace
_sl_ -> optional_single_line_whitespace
__ml__ -> mandatory_whitespace
_ -> optional_whitespace

mandatory_linebreak ->
    single_line_whitespace:*
    line_breaker
    whitespace_and_line_break:*

line_breaker -> MultiLineComment | MultiLineWhitespace | ";"

whitespace_and_line_break -> singular_whitespace | ";"

mandatory_single_line_whitespace -> single_line_whitespace:+
optional_single_line_whitespace -> single_line_whitespace:*

single_line_whitespace -> SingleLineWhitespace | MultiLineComment

optional_whitespace -> singular_whitespace:*
mandatory_whitespace -> singular_whitespace:+

singular_whitespace ->
    | SingleLineComment
    | MultiLineWhitespace
    | SingleLineComment
    | MultiLineComment

=== tokens ===

SingleLineWhitespace -> [ \t\r\f\v]+
MultiLineWhitespace -> [ \t\n\r\f\v]+
SingleLineComment -> \/\/[^\n]+
MultiLineComment -> \/\*.*?\*\/

Float -> [0-9]+\.[0-9]*
Int -> [0-9]+
String -> "<sequence of optionally escaped characters \
    and escaped special character placeholders \
    terminated by an unescaped '"'>
Null -> "null"
False -> "false"
True -> "true"

Name -> [a-zA-Z_][a-zA-Z0-9_]*
Id -> #[a-zA-Z0-9_]+
Class \.[a-zA-Z0-9_]+

LBrace -> "("
RBrace -> ")"
LBracket -> "["
RBracket -> "]"

Equal -> "="
Colon -> ":"
SemiColon -> ";"
Comma -> ","