parse-glycoct.md
In glyparse: Parsing Glycan Structure Text Representations

floating substituent positions preserve representable domains

Code
  normalize_floating_substituent_parents(c(1L, 2L), c(1L, 2L), "3/6S", c("1\r3",
    "2\r6"), context = "test substituent")
Condition
  Error:
  ! Can't represent the feasible parent-position combinations for a test substituent after excluding occupied carbon positions.

GlycoCT UND donor alternatives fail explicitly

Code
  parse_glycoct_und_block(und)
Condition
  Error in `parse_glycoct_und_block()`:
  ! GlycoCT UND linkages with alternative donor positions are not supported: "o(3+1|2)d"

GlycoCT UND parts require a feasible candidate parent

Code
  filter_glycoct_und_parents(1L, "b1-3", "1\r3")
Condition
  Error in `filter_glycoct_und_parents()`:
  ! No feasible parent remains for a GlycoCT UND part after excluding occupied acceptor positions.