Revert "- avoid parsing of invalid expression"
Revert "- avoid parsing of invalid expression"

This reverts commit ec85487f1ba9e79595a5bdbcb4be5e892255ccee.
jonasfoe/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,jonasfoe/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,jonasfoe/COPASI,copasi/COPASI,copasi/COPASI,copasi/COPASI