[lkb] Generator chart has edges for bare affixes

[Emily M. Bender]

Hi,

One of my students has created a grammar with an interesting
pathological property: when one uses it to generate, the chart
contains edges for affixes corresponding to many of the lexical
rules (as if they had attached to a null stem). Any idea
what might be causing this?


The grammar can be found here, if anyone wants to play with
it:

http://courses.washington.edu/ling567/arabic.tgz

A test case is:

?-i?dar ?-akal ?al-kizaz-a
1SG-can 1SG-eat the-glass-ACC
'I can eat glass'

Emily

[Ben Waldron]

We've experienced the same problem in a grammar developed by a student
in Trondheim. The problem disappeared when 'spelling-change-rule-p' was
redefined to correctly define all relevant inflectional rules as
spelling-change-rules -- in this case by defining the function to state
that 'lex-item' and it's subtypes (rather than 'word' and it's subtypes)
are spelling-change-rules:

(defun spelling-change-rule-p (rule)
(let ((rule-type (type-of-fs (tdfs-indef (rule-full-fs rule)))))
(when (or (eql rule-type 'lex-item) ;; <--
(subtype-p rule-type 'lex-item)) ;; <--
(let* ((mother (tdfs-indef (rule-full-fs rule)))
(morth (existing-dag-at-end-of mother *orth-path*))
(daughter (existing-dag-at-end-of mother '(ARGS FIRST)))
(dorth (existing-dag-at-end-of daughter *orth-path*)))
(not (eq morth dorth))))))

A question: Would using such a general type in the function above be
expected to lead to any problems elsewhere?

-Ben

Post by Emily M. Bender
Hi,
One of my students has created a grammar with an interesting
pathological property: when one uses it to generate, the chart
contains edges for affixes corresponding to many of the lexical
rules (as if they had attached to a null stem). Any idea
what might be causing this?
The grammar can be found here, if anyone wants to play with
http://courses.washington.edu/ling567/arabic.tgz
?-i?dar ?-akal ?al-kizaz-a
1SG-can 1SG-eat the-glass-ACC
'I can eat glass'
Emily