Appendix: NED Language Grammar¶

This appendix contains the grammar for the NED language.
In the NED language, space, horizontal tab and new line characters count as delimiters, so one or more of them is required between two elements of the description which would otherwise be unseparable.
The // symbol (two slashes) begin comments that extend to the end of the line.
The language is case sensitive.
Notation:
rule syntax is that of bison
uppercase words are terminals, lowercase words are nonterminals
NAME, STRINGCONSTANT, INTCONSTANT, REALCONSTANT represent identifier names and string, integer and real number literals (defined as in the C language, except that a 0 prefix does not stand for octal notation)
other terminals represent keywords in all lowercase
nedfile
        : definitions
        | %empty
        ;

definitions
        : definitions definition
        | definition
        ;

definition
        : packagedeclaration
        | import
        | propertydecl
        | fileproperty
        | channeldefinition
        | channelinterfacedefinition
        | simplemoduledefinition
        | compoundmoduledefinition
        | networkdefinition
        | moduleinterfacedefinition
        | ';'
        ;

packagedeclaration
        : PACKAGE dottedname ';'
        ;

dottedname
        : dottedname '.' NAME
        | NAME
        ;

import
        : IMPORT importspec ';'
        ;

importspec
        : importspec '.' importname
        | importname
        ;

importname
        : importname NAME
        | importname '*'
        | importname '**'
        | NAME
        | '*'
        | '**'
        ;

propertydecl
        : propertydecl\_header opt\_inline\_properties ';'
        | propertydecl\_header '(' opt\_propertydecl\_keys ')' opt\_inline\_properties ';'
        ;

propertydecl\_header
        : PROPERTY '@' PROPNAME
        | PROPERTY '@' PROPNAME '[' ']'
        ;

opt\_propertydecl\_keys
        : propertydecl\_keys
        | %empty
        ;

propertydecl\_keys
        : propertydecl\_keys ';' propertydecl\_key
        | propertydecl\_key
        ;

propertydecl\_key
        : property\_literal
        ;

fileproperty
        : property\_namevalue ';'
        ;

channeldefinition
        : channelheader '{'
            opt\_paramblock
          '}'
        ;

channelheader
        : CHANNEL NAME
           opt\_inheritance
        ;

opt\_inheritance
        : %empty
        | EXTENDS extendsname
        | LIKE likenames
        | EXTENDS extendsname LIKE likenames
        ;

extendsname
        : dottedname
        ;

likenames
        : likenames ',' likename
        | likename
        ;

likename
        : dottedname
        ;

channelinterfacedefinition
        : channelinterfaceheader '{'
            opt\_paramblock
          '}'
        ;

channelinterfaceheader
        : CHANNELINTERFACE NAME
           opt\_interfaceinheritance
        ;

opt\_interfaceinheritance
        : EXTENDS extendsnames
        | %empty
        ;

extendsnames
        : extendsnames ',' extendsname
        | extendsname
        ;

simplemoduledefinition
        : simplemoduleheader '{'
            opt\_paramblock
            opt\_gateblock
          '}'
        ;

simplemoduleheader
        : SIMPLE NAME
          opt\_inheritance
        ;

compoundmoduledefinition
        : compoundmoduleheader '{'
            opt\_paramblock
            opt\_gateblock
            opt\_typeblock
            opt\_submodblock
            opt\_connblock
          '}'
        ;

compoundmoduleheader
        : MODULE NAME
          opt\_inheritance
        ;

networkdefinition
        : networkheader '{'
            opt\_paramblock
            opt\_gateblock
            opt\_typeblock
            opt\_submodblock
            opt\_connblock
          '}'
        ;

networkheader
        : NETWORK NAME
          opt\_inheritance
        ;

moduleinterfacedefinition
        : moduleinterfaceheader '{'
            opt\_paramblock
            opt\_gateblock
          '}'
        ;

moduleinterfaceheader
        : MODULEINTERFACE NAME
           opt\_interfaceinheritance
        ;

opt\_paramblock
        : opt\_params
        | PARAMETERS ':'
          opt\_params
        ;

opt\_params
        : params
        | %empty
        ;

params
        : params paramsitem
        | paramsitem
        ;

paramsitem
        : param
        | property
        ;

param
        : param\_typenamevalue
        | parampattern\_value
        ;

param\_typenamevalue
        : param\_typename opt\_inline\_properties ';'
        | param\_typename opt\_inline\_properties '=' paramvalue opt\_inline\_properties ';'
        ;

param\_typename
        : opt\_volatile paramtype NAME
        | NAME
        ;

parampattern\_value
        : parampattern opt\_inline\_properties '=' paramvalue ';'
        ;

paramtype
        : DOUBLE
        | INT
        | STRING
        | BOOL
        | OBJECT
        | XML
        ;

opt\_volatile
        : VOLATILE
        | %empty
        ;

paramvalue
        : expression
        | DEFAULT '(' expression ')'
        | DEFAULT
        | ASK
        ;

opt\_inline\_properties
        : inline\_properties
        | %empty
        ;

inline\_properties
        : inline\_properties property\_namevalue
        | property\_namevalue
        ;

parampattern
        : pattern
        ;

pattern
        : pattern2 '.' pattern\_elem
        | pattern2 '.' TYPENAME
        ;

pattern2
        : pattern2 '.' pattern\_elem
        | pattern\_elem
        ;

pattern\_elem
        : pattern\_name
        | pattern\_name '[' pattern\_index ']'
        | pattern\_name '[' '*' ']'
        | '**'
        ;

pattern\_name
        : NAME
        | NAME '$' NAME
        | CHANNEL
        | '{' pattern\_index '}'
        | '*'
        | pattern\_name NAME
        | pattern\_name '{' pattern\_index '}'
        | pattern\_name '*'
        ;

pattern\_index
        : INTCONSTANT
        | INTCONSTANT '..' INTCONSTANT
        | '..' INTCONSTANT
        | INTCONSTANT '..'
        ;

property
        : property\_namevalue ';'
        ;

property\_namevalue
        : property\_name
        | property\_name '(' opt\_property\_keys ')'
        ;

property\_name
        : '@' PROPNAME
        | '@' PROPNAME '[' PROPNAME ']'
        ;

opt\_property\_keys
        : property\_keys
        ;

property\_keys
        : property\_keys ';' property\_key
        | property\_key
        ;

property\_key
        : property\_literal '=' property\_values
        | property\_values
        ;

property\_values
        : property\_values ',' property\_value
        | property\_value
        ;

property\_value
        : property\_literal
        | %empty
        ;

property\_literal
        : property\_literal CHAR
        | property\_literal STRINGCONSTANT
        | CHAR
        | STRINGCONSTANT
        ;

opt\_gateblock
        : gateblock
        | %empty
        ;

gateblock
        : GATES ':'
          opt\_gates
        ;

opt\_gates
        : gates
        | %empty
        ;

gates
        : gates gate
        | gate
        ;

gate
        : gate\_typenamesize
          opt\_inline\_properties ';'
        ;

gate\_typenamesize
        : gatetype NAME
        | gatetype NAME '[' ']'
        | gatetype NAME vector
        | NAME
        | NAME '[' ']'
        | NAME vector
        ;

gatetype
        : INPUT
        | OUTPUT
        | INOUT
        ;

opt\_typeblock
        : typeblock
        | %empty
        ;

typeblock
        : TYPES ':'
           opt\_localtypes
        ;

opt\_localtypes
        : localtypes
        | %empty
        ;

localtypes
        : localtypes localtype
        | localtype
        ;

localtype
        : propertydecl
        | channeldefinition
        | channelinterfacedefinition
        | simplemoduledefinition
        | compoundmoduledefinition
        | networkdefinition
        | moduleinterfacedefinition
        | ';'
        ;

opt\_submodblock
        : submodblock
        | %empty
        ;

submodblock
        : SUBMODULES ':'
          opt\_submodules
        ;

opt\_submodules
        : submodules
        | %empty
        ;

submodules
        : submodules submodule
        | submodule
        ;

submodule
        : submoduleheader ';'
        | submoduleheader '{'
          opt\_paramblock
          opt\_gateblock
          '}' opt\_semicolon
        ;

submoduleheader
        : submodulename ':' dottedname opt\_condition
        | submodulename ':' likeexpr LIKE dottedname opt\_condition
        ;

submodulename
        : NAME
        |  NAME vector
        ;

likeexpr
        : '<' '>'
        | '<' expression '>'
        | '<' DEFAULT '(' expression ')' '>'
        ;

opt\_condition
        : condition
        | %empty
        ;

opt\_connblock
        : connblock
        | %empty
        ;

connblock
        : CONNECTIONS ALLOWUNCONNECTED ':'
          opt\_connections
        | CONNECTIONS ':'
          opt\_connections
        ;

opt\_connections
        : connections
        | %empty
        ;

connections
        : connections connectionsitem
        | connectionsitem
        ;

connectionsitem
        : connectiongroup
        | connection opt\_loops\_and\_conditions ';'
        ;

connectiongroup
        : opt\_loops\_and\_conditions '{'
          connections '}' opt\_semicolon
        ;

opt\_loops\_and\_conditions
        : loops\_and\_conditions
        | %empty
        ;

loops\_and\_conditions
        : loops\_and\_conditions ',' loop\_or\_condition
        | loop\_or\_condition
        ;

loop\_or\_condition
        : loop
        | condition
        ;

loop
        : FOR NAME '=' expression '..' expression
        ;

connection
        : leftgatespec '-->' rightgatespec
        | leftgatespec '-->' channelspec '-->' rightgatespec
        | leftgatespec '<--' rightgatespec
        | leftgatespec '<--' channelspec '<--' rightgatespec
        | leftgatespec '<-->' rightgatespec
        | leftgatespec '<-->' channelspec '<-->' rightgatespec
        ;

leftgatespec
        : leftmod '.' leftgate
        | parentleftgate
        ;

leftmod
        : NAME vector
        | NAME
        ;

leftgate
        : NAME opt\_subgate
        | NAME opt\_subgate vector
        | NAME opt\_subgate '++'
        ;

parentleftgate
        : NAME opt\_subgate
        | NAME opt\_subgate vector
        | NAME opt\_subgate '++'
        ;

rightgatespec
        : rightmod '.' rightgate
        | parentrightgate
        ;

rightmod
        : NAME
        | NAME vector
        ;

rightgate
        : NAME opt\_subgate
        | NAME opt\_subgate vector
        | NAME opt\_subgate '++'
        ;

parentrightgate
        : NAME opt\_subgate
        | NAME opt\_subgate vector
        | NAME opt\_subgate '++'
        ;

opt\_subgate
        : '$' NAME
        | %empty
        ;

channelspec
        : channelspec\_header
        | channelspec\_header '{'
            opt\_paramblock
          '}'
        ;

channelspec\_header
        : opt\_channelname
        | opt\_channelname dottedname
        | opt\_channelname likeexpr LIKE dottedname
        ;

opt\_channelname
        : %empty
        | NAME ':'
        ;

condition
        : IF expression
        ;

vector
        : '[' expression ']'
        ;

expression
        : expr
        ;

expr
        : simple\_expr
        | functioncall
        | expr '.' functioncall
        | object
        | array
        | '(' expr ')'
        | expr '+' expr
        | expr '-' expr
        | expr '*' expr
        | expr '/' expr
        | expr '%' expr
        | expr '^' expr
        | '-' expr
                \_
        | expr '==' expr
        | expr '!=' expr
        | expr '>' expr
        | expr '>=' expr
        | expr '<' expr
        | expr '<=' expr
        | expr '<=>' expr
        | expr '=~' expr
        | expr '&&' expr
        | expr '||' expr
        | expr '##' expr
        | '!' expr
                \_
        | expr '&' expr
        | expr '|' expr
        | expr '#' expr
        | '~' expr
                \_
        | expr '<<' expr
        | expr '>>' expr
        | expr '?' expr ':' expr
        ;

functioncall
        : funcname '(' opt\_exprlist ')'
        ;

array
        : '[' ']'
        | '[' exprlist ']'
        | '[' exprlist ',' ']'
        ;

object
        : '{' opt\_keyvaluelist '}'
        | NAME '{' opt\_keyvaluelist '}'
        | NAME '::' NAME '{' opt\_keyvaluelist '}'
        | NAME '::' NAME '::' NAME '{' opt\_keyvaluelist '}'
        | NAME '::' NAME '::' NAME '::' NAME '{' opt\_keyvaluelist '}'
        ;

opt\_exprlist
        : exprlist
        | %empty
        ;

exprlist
        : exprlist ',' expr
        | expr
        ;

opt\_keyvaluelist
        : keyvaluelist
        | keyvaluelist ','
        | %empty
        ;

keyvaluelist
        : keyvaluelist ',' keyvalue
        | keyvalue
        ;

keyvalue
        : key ':' expr
        ;

key
        : STRINGCONSTANT
        | NAME
        | INTCONSTANT
        | REALCONSTANT
        | quantity
        | '-' INTCONSTANT
        | '-' REALCONSTANT
        | '-' quantity
        | NAN
        | INF
        | '-' INF
        | TRUE
        | FALSE
        | NULL
        | NULLPTR
        ;

simple\_expr
        : qname
        | operator
        | literal
        ;

funcname
        : NAME
        | BOOL
        | INT
        | DOUBLE
        | STRING
        | OBJECT
        | XML
        | XMLDOC
        ;

qname\_elem
        : NAME
        | NAME '[' expr ']'
        | THIS
        | PARENT
        ;

qname
        : qname '.' qname\_elem
        | qname\_elem
        ;

operator
        : INDEX
        | TYPENAME
        | qname '.' INDEX
        | qname '.' TYPENAME
        | EXISTS '(' qname ')'
        | SIZEOF '(' qname ')'
        ;

literal
        : stringliteral
        | boolliteral
        | numliteral
        | otherliteral
        ;

stringliteral
        : STRINGCONSTANT
        ;

boolliteral
        : TRUE
        | FALSE
        ;

numliteral
        : INTCONSTANT
        | realconstant\_ext
        | quantity
        ;

otherliteral
        : UNDEFINED
        | NULLPTR
        | NULL
        ;

quantity
        : quantity INTCONSTANT NAME
        | quantity realconstant\_ext NAME
        | INTCONSTANT NAME
        | realconstant\_ext NAME
        ;

realconstant\_ext
        : REALCONSTANT
        | INF
        | NAN
        ;

opt\_semicolon
        : ';'
        | %empty
        ;