babel

A Clojure library for generation and parsing of natural language expressions.

user> (require 'babel.italiano)
nil
user> (in-ns 'babel.italiano)
babel.italiano> (repeatedly #(-> {:root {:italiano {:italiano "sapere"}}
                                  :synsem {:cat :verb
				           :subcat []
                                           :sem {:subj {:pred :mario}
                                                 :tense :future
                                                 :pred :know-s}}
                                  :phrasal true
                                  :head {:phrasal false}
                                  :comp {:phrasal false}}
                                 (generate (grammar/medium))
                                 (morph)
                                 pprint
                                 time))
"Mario saprà"
"Elapsed time: 507.604262 msecs"
"Mario saprà"
"Elapsed time: 479.080943 msecs"
"Mario saprà"
"Elapsed time: 513.452862 msecs"
"Mario saprà"
"Elapsed time: 529.560233 msecs"
..

user> (require 'babel.english)
nil

;; generate a random expression in English
user> (babel.english/morph (babel.english/generate))
"your womens' new cities will lose me"

;; generate an infinite number of random expressions in English
user> (repeatedly #(println (babel.english/morph (babel.english/generate))))
Antonia and Luisa's first sigh
Gianluca's first pizza
you all turn a car down
Juan's short car was knowing the short bicycle

.. hit (control-c to stop) ..

;; generate the first 5 of all the expressions possible
user=> (map #(println (babel.english/morph %)) (take 5 (babel.english/generate-all)))
my first books
some first book
your first book
his first books
that first book
(nil nil nil nil nil)

The function babel.english/generate generates an English expression with no specified constraints: that is, the expression will only be constrained by the English grammar and lexicon defined by Babel.

The generated expression is a Clojure map representing the phrase structure of the expression. We pass this to the function babel.english/morph (short for "morphology") to convert this into a human readable string.

;; generate an English sentence about dogs eating
user> (-> {:synsem {:sem {:pred :eat :subj {:pred :dog}}}} babel.english/generate babel.english/morph)
"your first student's new dogs used to eat a small music's pizza"

Above, we now provide some constraints to the generation process. Specifically, we require that the expression must be about eating, and that the subject of the eating must be a dog or dogs (the value :dog is the semantics for the English word "dog").

;; generate a random expression in Italian
user> (require 'babel.italiano)
(-> :top babel.italiano/generate babel.italiano/morph)
"qualche neonato cittadino bene non bene non la sua"

;; generate an Italian sentence about dogs drinking
(-> {:synsem {:sem {:pred :drink :subj {:pred :dog}}}} babel.italiano/generate babel.italiano/morph)
"in delle brutto isole uno corto cane berrà la tua ensalata"
user> 

demo.sh

runs babel.english.demo/demo and will demonstrate some of the library's abilities to generate English expressions. Here is the output of a sample run of demo.sh

lein run -m babel.test.en/sentences 100

runs babel.english/sentences and will generate 100 random English sentences. Here is the output of a sample run.

lein test

will show a more in-depth verification of the library's behavior.

HPSG (Head Driven Phrase Structure Grammar)

Babel is based on a linguistic theory called HPSG. For more details please see:

• http://hpsg.stanford.edu/
• https://en.wikipedia.org/wiki/Head-driven_phrase_structure_grammar

Future Plans

Learn more about:

• https://en.wikipedia.org/wiki/Minimal_recursion_semantics
• https://en.wikipedia.org/wiki/Rhetorical_Structure_Theory

License

Copyright © 2016 Eugene Koontz

Distributed under the Eclipse Public License, the same as Clojure. Please see the epl-v10.html file at the top level of this repo.