PhonologicalRule

[dwhieb]

Create a new PhonologicalRule schema. Each Phonological Rule should have the following properties:

• name
• description: a prose description of this rule
• formula: a string representing the rule in Phonological Rule Notation:
  • https://en.wikipedia.org/wiki/Phonological_rule
  • https://sites.ualberta.ca/~kirchner/310/principlesforruleshandout.pdf
  • https://www.sfu.ca/~mcrobbie/Ling221/%236.pdf
  • https://www.vulgarlang.com/phonological-rules/

For now, we can leave the formula as a simple string. Later, we may implement input, output, and environment fields. This would be a fairly complex task though. We'd need to support:

• features (probably with a Phonological Features object, whose property values are Booleans)
• alpha/beta notation (probably by also allowing a or b as values of properties in the Phonological Features object)
• disjunction (with curly brackets)
• sequences (C_x; maybe just C/V followed immediately by a number)
• epenthesis / deletion (probably by allowing empty strings as input/output)
• boundaries (syllable σ or s; morpheme +; word #)
• natural classes (maybe): consonant C; vowel V; glide/semivowel W; sibilant S; rhotic R; lateral L; nasal N; maybe others
• both the input and output will probably need to be arrays, where each item in the array is either a phoneme (string), natural class (string), feature set (object), or boundary (string)

Take a look at this repo for implementation ideas: https://github.com/TriMill/sca

[dwhieb]

I think this issue is best split in two:

• phonologicalClass(es): A simple string indicating the phonological class a morpheme belongs to. Useful for indicating which phonological rules apply to a given morpheme without having to actually specify the details of the rule for every morpheme. The value should be the key of a PhonologicalRule object.
• PhonologicalRule: A schema object representing a phonological rule. This doesn't necessarily have to have a parent schema; it can live on its own. Each phonological rule should have a name / key, which can be used by the phonologicalClass attribute.