N-Triples
is
a
line-based,
plain
text
format
for
encoding
an
RDF
graph
.
Status
of
This
Document
This
is
a
preview
Do
not
attempt
to
implement
this
version
of
the
specification.
Do
not
reference
this
version
as
authoritative
in
any
way.
Instead,
see
https://w3c.github.io/rdf-n-triples/spec/
for
the
Editor's
draft.
This
section
describes
the
status
of
this
document
at
the
time
of
its
publication.
A
list
of
current
W3C
publications
and
the
latest
revision
of
this
technical
report
can
be
found
in
the
W3C
technical
reports
index
at
https://www.w3.org/TR/.
This
document
is
part
of
the
RDF
1.2
document
suite.
The
N-Triples
format
is
a
line-based
RDF
syntax
based
on
a
subset
of
Turtle
[
RDF12-TURTLE
].
Publication
as
an
Editor's
Draft
does
not
imply
endorsement
by
W3C
and
its
Members.
This
is
a
draft
document
and
may
be
updated,
replaced
or
obsoleted
by
other
documents
at
any
time.
It
is
inappropriate
to
cite
this
document
as
other
than
work
in
progress.
Cannot
GET
/uploads/bNfxDx/spec/common/related.html
/uploads/hugaIU/spec/common/related.html
1.
Introduction
This
section
is
non-normative.
This
document
defines
N-Triples,
a
concrete
syntax
for
RDF
[
RDF12-CONCEPTS
].
N-Triples
is
an
easy
to
parse
line-based
subset
of
Turtle
[
RDF12-TURTLE
].
The
syntax
is
a
revised
version
of
N-Triples
as
originally
defined
in
the
RDF
Test
Cases
[
RDF-TESTCASES
]
document.
Its
original
intent
was
for
writing
test
cases,
but
it
has
proven
to
be
popular
as
an
exchange
format
for
RDF
data.
N-Triples
triples
are
a
sequence
of
RDF
terms
representing
the
subject
,
predicate
,
and
object
of
an
RDF
Triple
.
These
may
be
separated
by
white
space
(spaces
U+0020
or
tabs
U+0009
).
This
sequence
is
terminated
by
a
'
.
'
(optionally
proceded
followed
by
white
space
and/or
a
comment),
and
a
new
line
(optional
at
the
end
of
a
document).
<http://one.example/subject1> <http://one.example/predicate1> <http://one.example/object1> . # comments here
# or on a line by themselves
_:subject1 <http://an.example/predicate1> "object1" .
_:subject2 <http://an.example/predicate2> "object2" .
N-Triples
triples
are
also
Turtle
simple
triples
,
but
Turtle
includes
other
representations
of
RDF
terms
and
abbreviations
of
RDF
Triples
.
When
parsed
by
a
Turtle
parser,
data
in
the
N-Triples
format
will
produce
exactly
the
same
triples
as
a
parser
for
the
N-triples
language.
The
RDF
graph
represented
by
an
N-Triples
document
contains
exactly
each
triple
matching
the
N-Triples
triple
production.
The
simplest
triple
statement
is
a
sequence
of
(
subject
,
predicate
,
and
object
)
terms,
and
terminated
by
'
.
'.
White
space
(spaces
U+0020
or
tabs
U+0009
)
may
surround
terms,
except
where
significant
as
noted
in
the
grammar
.
Comments
are
treated
as
white
space,
and
may
be
given
after
a
'
#
'
that
is
not
part
of
another
lexical
token
and
continue
to
the
end
of
the
line.
IRIs
may
be
written
only
as
absolute
IRIs.
IRIs
are
enclosed
in
'<'
and
'>'
and
may
contain
numeric
escape
sequences
(described
below).
For
example
<http://example.org/#green-goblin>
.
2.3
RDF
Literals
Literals
are
used
to
identify
values
such
as
strings,
numbers,
dates.
Literals
(Grammar
production
Literal
)
have
a
lexical
form
followed
by
a
language
tag,
a
datatype
IRI,
or
neither.
The
representation
of
the
lexical
form
consists
of
an
initial
delimiter
"
(
U+0022
),
a
sequence
of
permitted
characters
or
numeric
escape
sequence
or
string
escape
sequence,
and
a
final
delimiter.
Literals
may
not
contain
the
characters
"
,
LF
(
U+000A
),
or
CR
(
U+000D
)
except
in
their
escaped
forms.
In
addition
'
\
'
(
U+005C
)
may
not
appear
in
any
quoted
literal
except
as
part
of
an
escape
sequence
and
a
"
(
U+0022
)
character
can
only
be
included
in
a
quote
literal
using
an
escape
sequence.
The
corresponding
RDF
lexical
form
is
the
characters
between
the
delimiters,
after
processing
any
escape
sequences.
If
present,
the
language
tag
is
preceded
by
a
'
@
'
(
U+0040
).
If
there
is
no
language
tag,
there
may
be
a
datatype
IRI
,
preceded
by
'
^^
'
(
U+005E
U+005E
).
If
there
is
no
datatype
IRI
and
no
language
tag
it
is
a
simple
literal
and
the
datatype
is
http://www.w3.org/2001/XMLSchema#string
.
<http://example.org/show/218> <http://www.w3.org/2000/01/rdf-schema#label> "That Seventies Show"^^<http://www.w3.org/2001/XMLSchema#string> . # literal with XML Schema string datatype
<http://example.org/show/218> <http://www.w3.org/2000/01/rdf-schema#label> "That Seventies Show" . # same as above
<http://example.org/show/218> <http://example.org/show/localName> "That Seventies Show"@en . # literal with a language tag
<http://example.org/show/218> <http://example.org/show/localName> "Cette Série des Années Septante"@fr-be . # literal outside of ASCII range with a region subtag
<http://example.org/#spiderman> <http://example.org/text> "This is a multi-linenliteral with many quotes (""""")nand two apostrophes ('')." .
<http://en.wikipedia.org/wiki/Helium> <http://example.org/elements/atomicNumber> "2"^^<http://www.w3.org/2001/XMLSchema#integer> . # xsd:integer
<http://en.wikipedia.org/wiki/Helium> <http://example.org/elements/specificGravity> "1.663E-4"^^<http://www.w3.org/2001/XMLSchema#double> . # xsd:double
2.4
RDF
Blank
Nodes
RDF
blank
nodes
in
N-Triples
are
expressed
as
_:
followed
by
a
blank
node
label
which
is
a
series
of
name
characters.
The
characters
in
the
label
are
built
upon
PN_CHARS_BASE
,
liberalized
as
follows:
The
characters
_
and
[0-9]
may
appear
anywhere
in
a
blank
node
label.
The
character
.
may
appear
anywhere
except
the
first
or
last
character.
The
characters
-
,
U+00B7
,
U+0300
to
U+036F
and
U+203F
to
U+2040
are
permitted
anywhere
except
the
first
character.
A
fresh
RDF
blank
node
is
allocated
for
each
unique
blank
node
label
in
a
document.
Repeated
use
of
the
same
blank
node
label
identifies
the
same
RDF
blank
node.
Issue
2
:
Errata
from
1.1
propose
closing
Note
open
erratum
on
aligning
the
definition
and
production
for
blank
node
lables
with
Turtle.
3.
A
Canonical
form
of
N-Triples
This
section
defines
a
canonical
form
of
N-Triples
which
has
less
variability
in
a
completely
specified
layout.
The
grammar
for
the
language
is
the
same.
unchanged.
While
the
N-Triples
syntax
allows
choices
for
the
representation
and
layout
of
RDF
data,
the
canonical
form
of
N-Triples
provides
a
unique
syntactic
representation
of
any
triple.
Each
code
point
can
be
represented
by
only
one
of
UCHAR
Note
,
ECHAR
Even
when
not
explicitly
serializing
canonical
N-Triples,
implementers
are
encouraged
to
produce
this
form.
,
or
unencoded
character,
where
the
relevant
production
allows
for
a
choice
in
representation.
Each
triple
is
represented
entirely
on
a
single
line
with
specified
white
space.
Canonical
N-Triples
has
the
following
additional
constraints
on
layout:
The
white
White
space
following
MUST
NOT
be
used
except
after
subject
,
predicate
,
and
object
,
any
of
which
MUST
be
a
single
space,
space
(
U+0020
).
All
other
locations
that
allow
white
space
MUST
be
empty.
There
Literals
with
the
datatype
http://www.w3.org/2001/XMLSchema#string
MUST
NOT
be
no
comments.
use
the
datatype
IRI
part
of
the
literal
,
and
are
represented
using
only
STRING_LITERAL_QUOTE
.
Characters
MUST
NOT
be
represented
by
UCHAR
.
Within
STRING_LITERAL_QUOTE
,
only
the
characters
U+0022
,
U+0008
(
BS
),
U+005C
,
U+0009
(
HT
),
U+000A
,
(
LF
),
U+000C
(
FF
),
U+000D
are
(
CR
),
U+0022
(
"
),
and
U+005C
(
\
)
MUST
be
encoded
using
ECHAR
.
Characters
in
the
range
from
U+0000
to
U+001F
and
U+007F
(
DEL
)
that
are
not
represented
using
ECHAR
MUST
NOT
be
used
for
represented
by
UCHAR
.
All
other
characters
that
are
allowed
directly
in
STRING_LITERAL_QUOTE
.
MUST
be
represented
by
their
native
[
UNICODE
]
representation.
Issue
2
:
Errata
from
1.1
propose
closing
Note
open
errata:
32
–
Issues
with
N-Quads/N-Triples
canonicalization
.
33
–
Ambiguity
of
canonical
N-Triples
4.
Conformance
As
well
as
sections
marked
as
non-normative,
all
authoring
guidelines,
diagrams,
examples,
and
notes
in
this
specification
are
non-normative.
Everything
else
in
this
specification
is
normative.
The
key
words
MAY
,
MUST
,
MUST
NOT
,
and
SHOULD
in
this
document
are
to
be
interpreted
as
described
in
BCP
14
[
RFC2119
]
[
RFC8174
]
when,
and
only
when,
they
appear
in
all
capitals,
as
shown
here.
This
specification
defines
conformance
criteria
for:
A
conforming
N-Triples
document
is
a
Unicode
string
that
conforms
to
the
grammar
and
additional
constraints
defined
in
5.
N-Triples
Grammar
,
starting
with
the
ntriplesDoc
production
.
An
N-Triples
document
serializes
an
RDF
graph
.
A
conforming
N-Triples
parser
is
a
system
capable
of
reading
N-Triples
documents
on
behalf
of
an
application.
It
makes
the
serialized
RDF
graph
,
as
defined
in
6.
Parsing
,
available
to
the
application,
usually
through
some
form
of
API.
The
IRI
that
identifies
the
N-Triples
language
is:
http://www.w3.org/ns/formats/N-Triples
4.1
Media
Type
and
Content
Encoding
The
media
type
of
N-Triples
is
application/n-triples
.
The
content
encoding
of
N-Triples
is
always
UTF-8.
See
N-Triples
Media
Type
for
the
media
type
registration
form.
4.1.1
Other
Media
Types
N-Triples
has
been
historically
provided
with
other
media
types.
N-Triples
may
also
be
provided
as
text/plain
.
When
used
in
this
way
N-Triples
MUST
>
use
the
escaped
form
of
any
character
outside
US-ASCII.
As
N-Triples
is
a
subset
of
Turtle
an
N-Triples
document
MAY
also
be
provided
as
text/turtle
.
In
both
of
these
cases
the
document
is
not
an
N-Triples
document
as
an
N-Triples
document
is
only
provided
as
application/n-triples
.
A
blank
line
,
consisting
of
only
white
space
and/or
a
comment,
may
appear
wherever
a
triple
production
is
allowed,
and
are
treated
as
white
space.
Note
N-Triples
allows
only
horizontal
white
space
(tab
U+0009
or
space
U+0020)
as
compared
to
Turtle
[
RDF12-TURTLE
]
which
also
treats
LF
(
U+000A
)
and
CR
(
U+000D
)
as
white
space.
5.2
Comments
Comments
in
N-Triples
start
at
'
#
'
outside
an
IRIREF
or
STRING_LITERAL_QUOTE
,
and
continue
to
the
end
of
line
(marked
by
characters
CR
(
U+000D
or
LF
(
U+000A
))
or
end
of
file
if
there
is
no
end
of
line
after
the
comment
marker.
Comments
are
treated
as
white
space.
Escape
sequence
rules
are
the
same
as
Turtle
[
RDF12-TURTLE
].
However,
as
only
the
STRING_LITERAL_QUOTE
production
is
allowed
new
lines
in
literals
MUST
be
escaped.
Error
Cannot
GET
/uploads/bNfxDx/spec/ntriples-bnf.html
/uploads/hugaIU/spec/ntriples-bnf.html
6.
Parsing
Parsing
N-Triples
requires
a
state
of
one
item:
Map[string
->
blank
node
]
bnodeLabels
—
A
mapping
from
string
to
blank
node.
6.1
RDF
Term
Constructors
This
table
maps
productions
and
lexical
tokens
to
RDF
terms
or
components
of
RDF
terms
listed
in
section
:
The
literal
has
a
lexical
form
of
the
first
rule
argument,
STRING_LITERAL_QUOTE
,
and
either
a
language
tag
of
LANGTAG
or
a
datatype
IRI
of
iri
,
depending
on
which
rule
matched
the
input.
If
the
LANGTAG
rule
matched,
the
datatype
is
rdf:langString
and
the
language
tag
is
LANGTAG
.
If
neither
a
language
tag
nor
a
datatype
IRI
is
provided,
the
literal
has
a
datatype
of
xsd:string
.
The
STRING_LITERAL_QUOTE
production
allows
the
use
of
unescaped
control
characters.
Although
this
specification
does
not
directly
expose
this
content
to
an
end
user,
it
might
be
presented
through
a
user
agent,
which
may
cause
the
presented
text
to
be
obfuscated
due
to
presentation
of
such
characters.
N-Triples
is
a
general-purpose
assertion
language;
applications
may
evaluate
given
data
to
infer
more
assertions
or
to
dereference
IRIs
,
invoking
the
security
considerations
of
the
scheme
for
that
IRI.
Note
in
particular,
the
privacy
issues
in
[
RFC3023
]
section
10
for
HTTP
IRIs.
Data
obtained
from
an
inaccurate
or
malicious
data
source
may
lead
to
inaccurate
or
misleading
conclusions,
as
well
as
the
dereferencing
of
unintended
IRIs.
Care
must
be
taken
to
align
the
trust
in
consulted
resources
with
the
sensitivity
of
the
intended
use
of
the
data;
inferences
of
potential
medical
treatments
would
likely
require
different
trust
than
inferences
for
trip
planning.
The
N-Triples
language
is
used
to
express
arbitrary
application
data;
security
considerations
will
vary
by
domain
of
use.
Security
tools
and
protocols
applicable
to
text
(for
example,
PGP
encryption,
checksum
validation,
password-protected
compression)
may
also
be
used
on
N-Triples
documents
.
Security/privacy
protocols
must
be
imposed
which
reflect
the
sensitivity
of
the
embedded
information.
N-Triples
can
express
data
which
is
presented
to
the
user,
such
as
RDF
Schema
labels.
Applications
rendering
strings
retrieved
from
untrusted
N-Triples
documents
,
or
using
unescaped
characters,
SHOULD
use
warnings
and
other
appropriate
means
to
limit
the
possibility
that
malignant
strings
might
be
used
to
mislead
the
reader.
The
security
considerations
in
the
media
type
registration
for
XML
([
RFC3023
]
section
10)
provide
additional
guidance
around
the
expression
of
arbitrary
data
and
markup.
Multiple
IRIs
may
have
the
same
appearance.
Characters
in
different
scripts
may
look
similar
(for
instance,
a
Cyrillic
"о"
may
appear
similar
to
a
Latin
"o").
A
character
followed
by
combining
characters
may
have
the
same
visual
representation
as
another
character
(for
example,
LATIN
SMALL
LETTER
"E"
followed
by
COMBINING
ACUTE
ACCENT
has
the
same
visual
representation
as
LATIN
SMALL
LETTER
"E"
WITH
ACUTE).
Any
person
or
application
that
is
writing
or
interpreting
data
in
N-Triples
must
take
care
to
use
the
IRI
that
matches
the
intended
semantics,
and
avoid
IRIs
that
may
look
similar.
Further
information
about
matching
visually
similar
characters
can
be
found
in
Unicode
Security
Considerations
[
UNICODE-SECURITY
]
and
Internationalized
Resource
Identifiers
(IRIs)
[
RFC3987
]
Section
8.
C.
N-Triples
Internet
Media
Type,
File
Extension
and
Macintosh
File
Type
The
Internet
Media
Type
/
MIME
Type
for
N-Triples
is
"application/n-triples".
It
is
recommended
that
N-Triples
files
have
the
extension
".nt"
(all
lowercase)
on
all
platforms.
It
is
recommended
that
N-Triples
files
stored
on
Macintosh
HFS
file
systems
be
given
a
file
type
of
"TEXT".
This
information
that
follows
will
be
submitted
to
the
IESG
for
review,
approval,
and
registration
with
IANA.
Type
name:
application
Subtype
name:
n-triples
Required
parameters:
None
Optional
parameters:
None
Encoding
considerations:
The
syntax
of
N-Triples
is
expressed
over
code
points
in
Unicode
[
UNICODE
].
The
encoding
is
always
UTF-8
[
UTF-8
].
Unicode
code
points
may
also
be
expressed
using
an
\uXXXX
(U+0
to
U+FFFF)
or
\UXXXXXXXX
syntax
(for
U+10000
onwards)
where
X
is
a
hexadecimal
digit
[0-9A-F]
No
widely
deployed
applications
are
known
to
use
this
media
type.
It
may
be
used
by
some
web
services
and
clients
consuming
their
data.
Additional
information:
Magic
number(s):
None.
File
extension(s):
".nt"
Macintosh
file
type
code(s):
"TEXT"
Person
&
email
address
to
contact
for
further
information:
Eric
Prud'hommeaux
<eric@w3.org>
Intended
usage:
COMMON
Restrictions
on
usage:
None
Author/Change
controller:
The
N-Triples
specification
is
the
product
of
the
RDF
WG.
The
W3C
reserves
change
control
over
this
specifications.
D.
Acknowledgments
This
section
is
non-normative.
D.1
Acknowledgments
for
RDF
1.1
This
section
is
non-normative.
The
editor
of
the
RDF
1.1
edition
acknowledges
valuable
contributions
from
Gregg
Kellogg,
Eric
Prud'hommeaux,
Dave
Beckett,
David
Robillard,
Gregory
Williams,
Pat
Hayes,
Richard
Cyganiak,
Henry
S.
Thompson,
Peter
Ansell,
Evan
Patton
and
David
Booth.
This
specification
is
a
product
of
extended
deliberations
by
the
members
of
the
RDF
Working
Group.
It
draws
upon
the
earlier
specification
in
[
RDF-TESTCASES
],
edited
by
Dave
Beckett.
D.2
Acknowledgments
for
RDF
1.2
This
section
is
non-normative.
The
editors
of
the
RDF
1.2
edition
acknowledge
valuable
contributions
from
Andy
Seaborne.
In
addition
to
the
editors,
the
following
people
have
contributed
to
this
specification:
Pierre-Antoine
Champin
Error
Cannot
GET
/uploads/bNfxDx/spec/common/participants.html
/uploads/hugaIU/spec/common/participants.html
Editor's
note
Recognize
members
of
the
Task
Force?
Not
an
easy
to
find
list
of
contributors.
E.
Changes
between
RDF
1.1
and
RDF
1.2
This
section
is
non-normative.
Better
align
the
use
of
white
space
and
comments
with
[
RDF12-TURTLE
].
Removed
language
about
white
space
use
between
terminals
that
would
otherwise
be
(mis-)recognized,
is
this
can't
happen
in
N-Triples.
Clarify
the
use
of
blank
lines
,
including
those
composed
of
white
space
and/or
comments.
Comments
can
appear
at
the
end
of
a
triple
before
the
newline
as
was
already
evident
from
Example
1
.