module Porter2
Constants for the Porter 2 stemmer
Constants
- C
A non-vowel
- CW
A non-vowel other than w, x, or Y
- Double
Doubles created when adding a suffix: these are undoubled when stemmed
- SHORT_SYLLABLE
A specification for a short syllable.
A short syllable in a word is either:
-
a vowel followed by a non-vowel other than w, x or Y and preceded by a non-vowel, or
-
a vowel at the beginning of the word followed by a non-vowel.
(The original document is silent on whether sequences of two or more non-vowels make a syllable long. But as this specification is only used to find sequences of non-vowel - vowel - non-vowel - end-of-word, this ambiguity does not have an effect.)
-
- SPECIAL_CASES
Special-case stemmings
- STEP_1A_SPECIAL_CASES
Special case words to stop processing after step 1a.
- STEP_2_MAPS
Suffix transformations used in porter2_step2. (ogi, li endings dealt with in procedure)
- STEP_3_MAPS
Suffix transformations used in porter2_step3. (ative ending dealt with in procedure)
- STEP_4_MAPS
Suffix transformations used in porter2_step4. (ion ending dealt with in procedure)
- V
A vowel: a e i o u y
- Valid_LI
A valid letter that can come before ‘li’ (or ‘ly’)