rdflib Turtle output defines illegal _9 prefix

[ghost]

felik...@gmail.com, 2011-07-11T10:44:42.000Z

What steps will reproduce the problem?

I used rdfpipe to convert an n3 file to turtle format, resulting in the following:

@prefix _9: <http://data.linkedmdb.org/resource/movie/> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

<http://data.linkedmdb.org/resource/director/1> a
<http://data.linkedmdb.org/resource/movie/director>;
    rdfs:label "Cecil B. DeMille (Director)";
    _9:director_name "Cecil B. DeMille" .

However, _9 is not a valid prefix according to the standard:
See http://www.w3.org/TeamSubmission/turtle/#sec-grammar

[26]    nodeID  ::=     '_:' name
[27]    qname   ::=     prefixName? ':' name?
[33]    prefixName      ::=     ( nameStartChar - '_' ) nameChar*

so _9: is illegal

Either

_:BNode

or

abc_def:local

but not a leading _ for a prefix name.

What version of the product are you using? On what operating system?

$ rdfpipe --version
rdfpipe (using rdflib 3.0.0)

any feedback can be sent to feliksik AT gmail DOT com

Comment 1 by gromgull

Just to clarify, the problem here is that the namespace prefixes we generate ourselves are all ns1,ns2,etc. This problem occurs when the parsed file already contains prefixes like _9 - and they are not checked when producing turtle.

I imagine similar bugs may exist for all serialisations that allow prefixes.