# example structure for illustrating the language
primary
# the primary structure is indexed starting from 1
AAGACCUGCACGCUAGUU
declare
# these are the basic loops, identified by the starting index and
# the ending index
h1 = (2,14),
h2 = (3,13),
h3 = (4,7),
h4 = (9,12)
structure
# this is an expression using the nesting operator with a semantic error
h3 | h2 | h1 | h4
end