c = C | Ra;               # is_consonant
n = (ZWNJ? RS)? (N N?)?;  # is_consonant_modifier
z = ZWJ | ZWNJ;           # is_joiner
h = H | Coeng;            # is_halant_or_coeng
reph = Ra H | Repha;      # possible reph

cn = c ZWJ? n?;
forced_rakar = ZWJ H ZWJ Ra;
symbol = Symbol N?;
matra_group = z{0,3} M N? (H | forced_rakar)?;
# syllable_tail = (z? SM SM? ZWNJ?)? A{0,3} VD{0,2};
syllable_tail = (z? SM SM? ZWNJ?)? A{0,3};
place_holder = Placeholder | Dotted_Circle;
halant_group = z? h (ZWJ N?)?;
final_halant_group = halant_group | h ZWNJ;
medial_group = CM?;
halant_or_matra_group = (final_halant_group | (h ZWJ)? matra_group{0,4}) (Coeng (cn | V))?;

consonant_syllable = Repha? (cn halant_group){0,4} cn medial_group halant_or_matra_group syllable_tail;
vowel_syllable = reph? V n? (ZWJ | (halant_group cn){0,4} medial_group halant_or_matra_group syllable_tail);
standalone_cluster = (Repha? Placeholder | reph? Dotted_Circle) n? (halant_group cn){0,4} medial_group halant_or_matra_group syllable_tail;
symbol_cluster = symbol syllable_tail;
broken_cluster = reph? n? (halant_group cn){0,4} medial_group halant_or_matra_group syllable_tail;

main =
    consonant_syllable:consonant_syllable
  | vowel_syllable:vowel_syllable
  | standalone_cluster:standalone_cluster
  | symbol_cluster:symbol_cluster
  | broken_cluster:broken_cluster
;