def map_to_precursors_on_fly(seqs, names, loci, args):
precursor = precursor_sequence(loci, args.ref).upper()<EOL>dat = dict()<EOL>for s, n in itertools.izip(seqs, names):<EOL><INDENT>res = pyMatch.Match(precursor, str(s), <NUM_LIT:1>, <NUM_LIT:3>)<EOL>if res > -<NUM_LIT:1>:<EOL><INDENT>dat[n] = [res, res + len(s)]<EOL><DEDENT><DEDENT>logger.debug("<STR_LIT>" % (loci, len(dat), len(seqs)))<EOL>return dat<EOL>
map sequences to precursors with franpr algorithm to avoid writting on disk