apertium-yao.yao.rlx

# Firstly, we need to define what tags should be considered sentence delimiters. For this example, only full stop is set as delimiter.
DELIMITERS = "<.>" ;

# We can define sets for common tag clusters
LIST Case = (n s) (n p) ; # A set that matches either a Noun Singular or a Noun Plural

LIST Nominal = (n) (pro) ; # Nominal items

LIST Number = (sg) (pl) ; # Number

LIST NounClass = (cl1) (cl1a) (cl3) (cl5) (cl7) (cl9) (cl9a) (cl11) (cl12) (cl14) (cl15) (inf) (cl16) (cl17) (cl18) ; # Noun classes

LIST NounAgreementWord = (adj) ; # words that need to agree with nouns

SECTION
# If there is a singular noun to the right, I cannot be a verb or noun.
REMOVE (n) OR (v) IF (1 (n s)) ;

# If I am a verb, adjective, demonstrative, or associative inflected to agree with a certain noun class, select me if the noun or pronoun preceding me is of that class.
SELECT $$NounClass IF (0 NounAgreementWord) (-1 Nominal + $$NounClass ) ; 

# If I am verb, adjective, demonstrative, or associative inflected to agree with a certain number, select me if the noun or pronoun preceding me is of that number.
SELECT $$Number IF (0 NounAgreementWord) (-1 Nominal + $$Number ) ; 

# If I am a noun that can be singular or plural and am followed by a singular adjective, I cannot be plural
REMOVE (n pl) IF (0 (n sg)) (0 (n pl)) (1 (adj sg)) ;

# If I am a noun that can be singular or plural and am follwed by a plural adjective, I cannot be singular
REMOVE (n sg) IF (0 (n sg)) (0 (n pl)) (1 (adj pl)) ;

# If there is a conjunction followed by a certain cohort of the same CASE as me, choose me.
SELECT $$Case IF (1 (cnjcoo) LINK 1C $$Case) ;

# Resources:
# http://visl.sdu.dk/cg3.html
# http://groups.google.com/group/constraint-grammar
# http://kevindonnelly.org.uk/2010/05/constraint-grammar-tutorial/
# http://wiki.apertium.org/wiki/Constraint_Grammar
# http://wiki.apertium.org/wiki/Apertium_and_Constraint_Grammar