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.

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 DesignDecisions.md.