CJK Width Token Filteredit
The cjk_width token filter normalizes CJK width differences:
- Folds fullwidth ASCII variants into the equivalent basic Latin
- Folds halfwidth Katakana variants into the equivalent Kana
This token filter can be viewed as a subset of NFKC/NFKD
Unicode normalization. See the analysis-icu plugin
for full normalization support.