I have implemented a nested logical form generator, built around the core relations in propS. It leverages propS's core ability to identify (possibly multiple) propositions in a sentence, while removing much of the syntactical clutter that plagues other approaches.
(My work was fairly straightforward -- simply about generating a nested json (unordered) structure, with explicit cross-references in cases where the same node is targeted by multiple parents.)
{'lf': {'comp': {'dobj': 'issue', 'pred': 'combat', 'subj': {'xref': '21'}},
'iobj': {'dep': {'conj_and': ['staffing',
{'mod': ['national', 'specific'],
'word': ['anti-drugs', 'agency']}],
'pred': 'and'},
'prep_in': ['security', 'force'],
'word': 'increase'},
'pred': 'proposed',
'subj': {'word': ['Mr', 'Macri'], 'xtarget': '21'}},
'sentence': 'Mr Macri has proposed an increase in security force staffing , and a specific national anti-drugs agency to combat the issue .'}
{'lf': {'comp': [{'comp': {'pred': 'rule', 'prep_by': 'decree'},
'dobj': {'mod': 'presidential', 'word': 'power'},
'pred': 'limit',
'subj': {'xref': '25'}},
{'dobj': {'prep_of': {'conj_and': [{'mod': {'pred': 'stalled'},
'word': ['reform',
'agenda']},
{'mod': 'legislative',
'word': 'gridlock'}],
'pred': 'and'},
'word': 'possibility'},
'pred': 'creating'}],
'pred': 'seeks',
'subj': {'word': 'legislature', 'xtarget': '25'}},
'sentence': 'The legislature seeks to limit presidential power to rule by decree , creating the possibility of legislative gridlock and a stalled reform agenda .'}
{'lf': [{'mod': 'also',
'pred': 'modified',
'prepc_by': {'dobj': [{'word': ['Media', 'Law'], 'xtarget': '71'},
{'prep_of': {'mod': [{'mod': 'more',
'word': 'controversial'},
{'pred': 'passed',
'prep_by': ['Fernandez',
'administration']}],
'word': 'reforms'},
'word': 'one',
'xtarget': '59'}],
'word': 'decree'},
'subj': ['Mr', 'Macri']},
{'pred': 'SameAs', 'sameAs_arg': [{'xref': '71'}, {'xref': '59'}]}],
'sentence': 'Mr Macri also modified by decree the Media Law , one of the more controversial reforms passed by the Fernandez administration .'}
{'lf': {'dobj': {'comp': {'obj': ['decree', 'powers'],
'pred': 'eliminated',
'prep_at': 'point',
'prep_during': ['President',
'Mauricio',
'Macris',
'administration']},
'word': 'risk'},
'pred': 'raises',
'subj': {'prep_of': {'prep': {'pcomp': {'pobj': {'mod': 'dominant',
'word': ['Peronist',
'party']},
'word': 'outside'},
'word': 'from'},
'word': 'president'},
'word': 'election'}},
'sentence': 'The election of a president from outside the dominant Peronist party raises the risk that decree powers will be eliminated at some point during President Mauricio Macris administration .'}
Note — this one is quite complicated! The graph has a cycle in it.
{'lf': [{'prep_of': {'xref': '112'},
'top': 0,
'word': 'number',
'xtarget': '110'},
{'dobj': {'xref': '112'},
'pred': 'overturned',
'subj': ['Mr', 'Macri'],
'xtarget': '113'},
{'mod': {'xref': '113'},
'prep_on': ['media', 'holdings'],
'top': 0,
'word': 'restrictions',
'xtarget': '112'},
{'dobj': {'xref': '110'}, 'pred': 'placed', 'subj': 'law'}],
'sentence': 'The law had placed a number of restrictions on media holdings , which Mr Macri has overturned .'}