prttl - Prettier Turtle

prttl is an auto formatter (aka pretty printer) for RDF Turtle. It is optimized for diff minimization, which is of value when developing Turtle (e.g. an Ontology) in a git repo.

NOTE
If you are comparing this to other Turtle pretty printers, you probably want to have a look at our design decisions.

Installation

It is distributed on Crates.io, and can be installed with cargo install prttl. Make sure you have cargo installed before doing that.

Usage

To use it:

prttl MY_TURTLE_FILE.ttl

It is also possible to check if formatting of a given file is valid according to the formatter using:

prttl --check MY_TURTLE_FILE.ttl

If the formatting is not valid, a patch to properly format the file is written to the standard output.

It is also possible to check a complete directory (and its subdirectories):

prttl MY_DIR

All the options:

$ prttl
Takes RDF data as input (commonly a Turtle file), and generates diff optimized RDF/Turtle, using a lot of new-lines. One peculiarity of this tool is, that it removes (Turtle-syntax) comments. We do this, because we believe that all comments should rather be encoded into triples, and we celebrate this in our own data, specifically our ontologies. More about this: <https://codeberg.org/elevont/cmt-ont>

Usage: prttl [OPTIONS] <FILE_OR_DIR>...

Arguments:
  <FILE_OR_DIR>...
          Source RDF file(s) or director(y|ies) containing Turtle files to format

Options:
      --canonicalize
          Whether to canonicalize the input before formatting. This refers to <https://www.w3.org/TR/rdf-canon/>, and effectively just label the blank nodes in a uniform way.

  -c, --check
          Do not edit the file but only check if it already applies this tools format

  -f, --force
          Forces overwriting of the output file, if it already exists, which includes the case of the input and output file being equal

  -l, --label-all-blank-nodes
          Whether to use labels for all blank nodes, or rather maximize nesting of them. NOTE That blank nodes referenced in more then one place can never be nested.

  -i, --indentation <NUM>
          Number of spaces per level of indentation

          [default: 2]

      --no-prtr-sorting
          Whether to disable sorting of blank nodes using their `prtr:sortingId` value, if any. [`prtr`](https://codeberg.org/elevont/prtr) is an ontology concerned with [RDF Pretty Printing](https://www.w3.org/DesignIssues/Pretty.html).

      --no-sparql-syntax
          Whether to use SPARQL-ish syntax for base and prefix, or the traditional Turtle syntax. - SPARQL-ish: ```turtle BASE <http://example.com/> PREFIX foaf: <http://xmlns.com/foaf/0.1/> ``` - Traditional Turtle: ```turtle @base <http://example.com/> . @prefix foaf: <http://xmlns.com/foaf/0.1/> . ```

      --pred-order [<PREDICATE>...]
          Sets a custom order of predicates to be used for sorting.
          Predicates that match come first; in the provided order.
          Predicates that do not match come afterwards; in alphabetical order.

          You may specify predicate names as absolute IRIs or as prefixed names.
          Only direct matches are considered; meaning: No type inference is conducted.

      --pred-order-preset <PREDICATE_ORDER_PRESET>
          Sets a predefined order of predicates to be used for sorting.
          Predicates that match come first; in the provided order.
          Predicates that do not match come afterwards; in alphabetical order.

          You may specify predicate names as absolute IRIs or as prefixed names.
          Only direct matches are considered; meaning: No type inference is conducted.

          [possible values: owl, skos, shacl, shex, rdf]

  -n, --single-leafed-new-lines
          Whether to move a single/lone predicate-object pair or object alone onto a new line

      --subj-type-order [<SUBJECT_TYPE>...]
          Sets a custom order of subject types to be used for sorting.
          Subjects with a matching type come first; in the provided order.
          Subjects without any matching type come afterwards; in alphabetical order.

          You may specify subject type names as absolute IRIs or as prefixed names.
          Only direct matches are considered; meaning: No type inference is conducted.

      --subj-type-order-preset <SUBJECT_TYPE_ORDER_PRESET>
          Sets a predefined order of subject types to be used for sorting.
          Subjects with a matching type come first; in the provided order.
          Subjects without any matching type come afterwards; in alphabetical order.

          Only direct matches are considered; meaning: No type inference is conducted.

          [possible values: owl, skos, shacl, shex, rdf]

  -q, --quiet
          Minimize or suppress output to stdout, and only shows log output on stderr.

  -v, --verbose
          more verbose output (useful for debugging)

  -V, --version
          Print version information and exit. May be combined with -q,--quiet, to really only output the version string.

  -h, --help
          Print help (see a summary with '-h')

Format

prttl is in development and its output format is not stable yet.

Sample Output

@prefix ex: <http://example.com/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<s>
  a ex:Foo ;
  <p>
    "foo"@en ,
    (
      +01
      +1.0
      1.0e0
    ) ;
  .

[
  ex:p
    ex:o ,
    ex:o2 ;
  ex:p2 ex:o3 ;
  ex:p3 true ;
] .

Features

• Removes all Turtle syntax comments.
• Checks that the file is valid.
• Maintains consistent indentation and new-lines.
• Normalizes string and IRI escapes as much as possible.
• Enforces the use of " instead of ' in literals.
• Uses literals short notation for booleans, integers, decimals and doubles when it keeps the lexical representation unchanged.
• Uses a for rdf:type where possible.

A much more detailed account and reasoning behind what this tool does can be found in design decisions.