# MRS, DMRS not displayed in LTDB

**URL:** <https://delphinqa.ling.washington.edu/t/mrs-dmrs-not-displayed-in-ltdb/986>\
**Category:** LTDB\
**Created:** [November 9, 2023, 4:20pm UTC](https://delphinqa.ling.washington.edu/t/mrs-dmrs-not-displayed-in-ltdb/986 "2023-11-09T16:20:23Z")\
**Posts on this page:** 1\
**Showing post:** 6

<div class="post-metadata">

**Author:** ![goodmami](https://delphinqa.ling.washington.edu/letter_avatar_proxy/v4/letter/g/b5e925/32.png) [@goodmami](https://delphinqa.ling.washington.edu/u/goodmami)\
**Post date:** [November 9, 2023, 10:39pm UTC](https://delphinqa.ling.washington.edu/t/mrs-dmrs-not-displayed-in-ltdb/986/6 "2023-11-09T22:39:24Z")

</div>

According to the grammar @arademaker linked to, role-argument values must be variables, and `link` and `*top*` are not variables. PyDelphin, which LTDB uses under the hood (at least an old version), is more permissive about loading and dumping such MRSs as role-argument values can be any symbol, but any task that involves interpretation of that MRS, such as conversion to DMRS, will likely fail.

```python
>>> from delphin.codecs import simplemrs
>>> s = """[LTOP: h0 INDEX: e2 [ e SF: prop TENSE: untensed MOOD: indicative] RELS: < [named_rel<-1:-1> LBL: h4 CARG: "pitágoras" WLINK: list CFROM: *top* CTO: *top* ARG0: x3 ARG1: u9] ["_ladrar_v_rel"<-1:-1> LBL: h1 WLINK: list CFROM: *top* CTO: *top* ARG0: e2 ARG1: x3] > HCONS: < h0 qeq h1 > ]"""
>>> m = simplemrs.loads(s)
>>> m
[<MRS object (named _ladrar_v) at 140321187189856>]
>>> print(simplemrs.dumps(m))
[TOP: h0 INDEX: e2 [ e SF: prop TENSE: untensed MOOD: indicative] RELS: < [named<-1:-1> LBL: h4 ARG0: x3 ARG1: u9 CFROM: *top* CTO: *top* WLINK: list CARG: "pitágoras"] [_ladrar_v<-1:-1> LBL: h1 ARG0: e2 ARG1: x3 CFROM: *top* CTO: *top* WLINK: list] > HCONS: < h0 qeq h1 > ]
>>> from delphin import dmrs
>>> dmrs.from_mrs(m[0])
Traceback (most recent call last):
  [...]
ValueError: Invalid variable string: list

```

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