# Configuration Options

These options can be set in `conf.py` along with the other Sphinx configuration settings.

## Input Options

`spelling_lang='en_US'`
  String specifying the language, as understood by PyEnchant and enchant. Defaults to `en_US` for US English.
`tokenizer_lang='en_US'`
  String specifying the tokenizer language as understood by PyEnchant and enchant. Defaults to `en_US` for US English.
`spelling_word_list_filename='spelling_wordlist.txt'`
  String specifying a file containing a list of words known to be spelled correctly but that do not appear in the language dictionary selected by `spelling_lang`. The file should contain one word per line. Refer to the PyEnchant tutorial for details.

## Output Options

`spelling_show_suggestions=False`
  Boolean controlling whether suggestions for misspelled words are printed. Defaults to False.

## Word Filters

Enable or disable the built-in filters to control which words are returned by the tokenizer to be checked.

`spelling_ignore_pypi_package_names=False`
  Boolean controlling whether words that look like package names from PyPI are treated as spelled properly. When `True`, the current list of package names is downloaded at the start of the build and used to extend the list of known words in the dictionary. Defaults to `False`.
`spelling_ignore_wiki_words=True`
  Boolean controlling whether words that follow the CamelCase conventions used for page names in wikis should be treated as spelled properly. Defaults to `True`.
`spelling_ignore_acronyms=True`
  Boolean controlling treatment of words that appear in all capital letters, or all capital letters followed by a lower case `s`. When `True`, acronyms are assumed to be spelled properly. Defaults to `True`.
`spelling_ignore_python_builtins=True`
  Boolean controlling whether names built in to Python should be treated as spelled properly. Defaults to `True`.
`spelling_ignore_importable_modules=True`
  Boolean controlling whether words that are names of modules found on `sys.path` are treated as spelled properly. Defaults to `True`.
`spelling_filters=[]`
  List of filter classes to be added to the tokenizer that produces words to be checked. The classes should be derived from `enchant.tokenize.Filter`. Refer to the PyEnchant tutorial for examples.

## Private Dictionaries

There are two ways to provide a list of known good words. The `spelling_word_list_filename` option (described above) specifies the name of a plain text file containing one word per line. All of the words in the file are assumed to be spelled correctly and may appear in any part of the document being processed.

The `spelling` directive can be used to create a list of words known to be spelled correctly within a single file. For example, if a document refers to a person or project by name, the name can be added to the list of known words for just that document.

    .. spelling::

       Docutils
       Goodger

## Custom Word Filters

The PyEnchant tokenizer supports a “filtering” API for processing words from the input. Filters can alter the stream of words by adding, replacing, or dropping values.

New filters should be derived from `enchant.tokenize.Filter` and implement either the `_split()` method (to add or replace words) or `_skip()` (to treat words as being spelled correctly). For example, this `AcronymFilter` skips words that are all uppercase letters or all uppercase with a trailing lowercase “s”.

    class AcronymFilter(Filter):
        """If a word looks like an acronym (all upper case letters),
        ignore it.
        """

        def _skip(self, word):
            return (word.isupper() # all caps
                    or
                    # pluralized acronym ("URLs")
                    (word[-1].lower() == 's'
                     and
                     word[:-1].isupper()
                     )
                    )

To be used in a document, the custom filter needs to be installed somewhere that Sphinx can import it while processing the input files. The Sphinx project’s `conf.py` then needs two changes.

1. Import the filter class.
2. Add the filter class to the `spelling_filters` configuration variable.

    from mymodule import MyFilter

    spelling_filters = [MyFilter]

See also

- Creating a Spelling Checker for reStructuredText Documents
- PyEnchant tutorial