Difference between revisions of "internal grammar of tags"

Tense grammar simplification proposal, by la xorxes.

Current grammar

```tense-modal = simple-tense-modal # | FIhO # selbri /FEhU#/

simple-tense-modal = [NAhE] [SE] BAI [NAI] [KI]
| [NAhE] (time [space] | space [time]) & CAhA [KI]
| KI
| CUhE

time = ZI & time-offset ... & ZEhA [[PU [[NAI]] & interval-property ...

time-offset = PU [NAI] [ZI]

space = VA & space-offset ... & space-interval & (MOhI space-offset)

space-offset = FAhA [NAI] [VA]

space-interval = ((VEhA & VIhA) [[FAhA [[NAI]]) & space-int-props

space-int-props = (FEhE interval-property) ...

interval-property = number ROI [NAI] | TAhE [NAI] | ZAhO [NAI]
```

Proposed grammar

```tense-modal = ([NAhE] [SE] tag-unit [NAI] #) ...

tag-unit = BAI
| CAhA
| CUhE
| KI
| ZI
| PU
| VA
| [MOhI] FAhA
| ZEhA
| VEhA
| VIhA
| [FEhE] number ROI
| [FEhE] TAhE
| [FEhE] ZAhO
| FIhO # selbri /FEhU/
```

Rationale

SE-conversion

Every tag-unit can be used as a tag, and therefore as a connective. It is arbitrary and inconvenient that SE is currently disallowed with some tags.

NAhE

NAhE PU, NAhE CAhA and NAhE PU CAhA are all allowed, but NAhE PU NAhE CAhA is not. This is arbitrary and inconvenient. Similarly for other combinations.

Order of units

co'a na'o broda (starting to typically broda) is allowed, but na'o co'a broda (typically starting to broda) is not. It will be accepted by the parser, but parsed as na'oku co'a broda. Similarly for all other order restrictions. Note: arbitrary combinations of tag-units are already allowed in selbri-tags as long as there is an intervening ja'a, for example: na'o ja'a co'a broda is allowed, without kus.

NAI

There's no good reason to allow it selectively here and there instead of everywhere.

Backwards compatibility

Fully compatible. Everything currently grammatical remains grammatical.

Notes

1. In the original proposal I had kept PU [ZI], FAhA [VA], ZEhA [PU], VEhA [FAhA] and VIhA [FAhA] as separate forms because I thought their compound meaning might follow special compositional rules. I don't think that is the case, though. Just as the Imaginary Journey composition follows the ordinary left-to-right scope rule, these compounds follow the rule too. For example, ze'u pu indicates a long duration of an event in the past of some reference point, where the event is in the past for the whole duration.
2. Originally I had only redefined the simple-tense-modal, but since the exclusion of FIhO-modals from the general case was due to the LR(1) restriction which no longer applies, we can now generalize the full tense-modal.