[REBOL] Re: [REBOL parse] Parsing AEIOU and sometimes Y
From: gregg::pointillistic::com at: 1-May-2007 17:00
Hi Ed,
EOC> "A consonant in a word is a letter other than A, E, I, O or U, and other
EOC> than Y preceded by a consonant."
EOC> In other words, the letter "y" is considered to be a consonant when it
EOC> is preceded by a vowel. When "y" is preceded by another consonant is
EOC> to be interpreted as a vowel.
Having not read the algorithm spec, is this on track?
vow: charset "aeiouAEIOU"
y: charset "yY"
con: exclude charset [#"a" - #"z" #"A" - #"Z"] union vow y
ycon: [vow y (print "y = consonant")]
yvow: [con y (print "y = vowel")]
just-y: [y (print "y = consonant")]
rule: [some [yvow | ycon | con | vow | just-y]]
parse "toy" rule ; y = consonant
parse "crazy" rule ; y = vowel
parse "crybaby" rule ; y = vowel; y = vowel
parse "yay" rule ; y = consonant ; y = consonant
parse "yoyo" rule ; y = consonant ; y = consonant
-- Gregg