quant_any="*"
quant_opt="?"
quant_some="+"
quant_num="{1,2}"

branch="|a"
pos_group="[a]"
neg_group="[^a]"

cat_letter="\\p{L}"
cat_mark="\\p{M}"
cat_number="\\p{N}"
cat_punct="\\p{P}"
cat_sym="\\p{S}"
cat_sep="\\p{Z}"
cat_other="\\p{C}"