8 Dec
2007
8 Dec
'07
12:17 a.m.
Please find below the latest draft of the MSE format
There is a new mse element, annotations, which can be used twofold
(1) To structure mse files into multiple documents. For example an
mse file may contain an @mse header document and both a @metamodel
and @model document, or even multiple @version1 @version2 ...
documents. The only reserved annotation would be @mse for the leading
header document.
So a valid document could eg look like this
@mse ((MSE.File
(metamodel 'http://moose.unibe.ch/spec/famix/3.0')
(model '@model'))
@model
((FAMIX.Package (id: 1)
(name 'LAN')
(classes
(FAMIX.Class ...
...
...
))))
(2) Annotations for elements. Attribute names may start with an @ to
indicate an attribute not conforming to the metamodel, for example
the longDesc of a Moose measurement, or the category of a Moose meny
entry would use this feature. But also the variable indexed slots of
Magritte elements.
(MA.Element
(name 'ABC')
(attr 0.5 0.75 -1 0.2)
(@1 'foo')
(@2 'bar')
(@3 nil)
(@4 'qux'))
Also there are two new primitives
- Nil
- Datetime
Nil is not to be confused with unset values, which may have a default
value different from nil
(...
absent = default value
(attr ) = default value
(attr nil) = nil value
(attr "..some..") = some value
...)
Similar to SAX, there is a ParserClient interface for reading MSE
documents using callbacks. This interface allows an application to
register for MSE document parsing. The sequence of callbacks is
limited to the following protocol
MAIN := beginFile ( annotation* beginDocument ELEM* endDocument )*
endFile
ELEM := beginElement serial? (beginAttribute ( primitive | reference
| ELEM )* endAttribute) endElement
which is based on this grammer and tokens
root := fragment | file
fragment := elementNode
file := document*
document := annotation* "(" elementNode* ")"
annotation := AT_NAME
elementNode := "(" elementName serial? attributeNode* ")"
elementName := NAME
attributeNode := "(" attributeName valueNode* ")"
attributeName := NAME | AT_NAME
valueNode := primitive | id-reference | reference | elementNode
primitive := STRING | NUMBER | BOOLEAN | DATE | NIL
serial := "(" "id:" INTEGER ")"
id-reference := "(" "idref:" INTEGER ")"
reference := "(" "ref:" NAME ")"
Breaks input-stream into tokens. Accepts the following grammar
Tokens
Open ::= "("
Close ::= ")"
AtName ::= "@" ( Letter | Digit )+
Keyword ::= "id:" | "idref:" | "ref:"
Name ::= Letter ( Letter | Digit )* ( "." ( Letter | Digit )+ )*
String ::= ( "'" [ˆ']* "'" )+
Boolean ::= "true" | "false"
Nil ::= "nil"
Date ::= Digit{4} "-" Digit{2} "-" Digit{2} ( ","
Digit{2}
":" Digit{2} ":" Digit{2} )
Number ::= "-"? Digit+ ( "." Digit+ )? ( "e" (
"-"? Digit+ ))?
Terminals
Digit ::= [0-9]
Letter ::= [a-zA-Z_]
Whitespace
Whitespace ::= Space Tab ecetera...
Comment ::= "\"" [ˆ"] "\""
----
What do you think?
AA