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Config Language Reference

For a general introduction to the configuration language design and semantics, head over to this section.

General syntax​

A dunolint config is made of a single well-formed s-expression (sexp). It defines a list of rules and config values.

Predicates​

Written as (name ARGS). Refer to the documentation for each predicate for details.

Blang​

The syntax for blang constructs is: true, false, (if _), (or _), (and _), and (not _).

or and and have variable arity and require no extra parenthesis around the list of their arguments.

Examples:

  • (not (has_field lint))
  • (and (stanza library) (has_field preprocess))

Rules​

Rule(T)::
 | LEAF
 | (cond CLAUSES)

CLAUSE::
 | CONDITION * T

LEAF:
 | (enforce CONDITION)
 | return
 | skip_subtree

Examples:

You can look for Dunolint's dunolint configuration that is located in the repository, as well as the repo test suite.

Config​

The entire config is a record with the following fields:

skip_subtree (optional). A single rule which is not allowed to enforce any condition, but rather serves to perform skip_subtree.

rules a list of rules.

((skip_subtree
   RULE
 )
 (rules (
   RULE
   RULE
   ...
 )))

Selectors​

Head over to the next pages for selectors dedicated to a certain type of files. In addition to them, the following selectors are common to all fragments:

path​

The path selector refers to either the path of the directory currently visited by the linter, or the path of the files containing the fragment currently being linted, depending on the context.

glob​

(glob GLOB) defines a predicate whose domain is the selected path, based on the evaluation of the GLOB pattern against the string representation of the path.

When used in a skip_subtree rule, it selects the directory visited and in this case the path ends with a trailing / character.

Examples​

Any file present directly under a directory named test, which can be present anywhere in the tree

(path (glob **/test/*)

A few directories commonly ignored at the root of the repo

(path (or (glob .git/) (glob _build/) (glob _opam/)))