1 _____________________________________________________________________________
4 - do Forest/Tree still need a Region?
6 - evil problems with (x y? z /ws)
7 - ParseFailed, GSS, Walk, Parser, Sequence, Forest
11 - grammar highlighting?
12 - comment indentation vs block indentation?
14 - recursive { { foo } }
16 ______________________________________________________________________________
19 - finalize metagrammar and rdp-op's
24 - RFC2822 (email message/headers)
25 - clean up the whole Walk situation (?)
28 ______________________________________________________________________________
31 - serialization of parse tables
33 - "ambiguity modulo dropped fragments"?
34 - can this be checked statically?
35 - eliminated statically?
37 - substring parsing for better error messages
40 - "Regular Right Part" grammars (NP Chapman, etc)
41 - Attribute unification
43 - inference of rejections for literals
44 - "prefer whitespace higher up" (?)
46 - Labeled edges on trees (associate a label with each slot in the
47 child array in Forest.Body? might make equality tough) --
48 equivalent to Feature Structures. Colon-labeling.
50 ______________________________________________________________________________
53 - Partly-Linear-PATR? (O(n^6) unification grammar)
55 - Implement a k-token peek buffer (for each state, see if it "dead
56 ends" during the next k Phases based solely on state -- ignoring
59 - Arrange for the SPPF corresponding to dropped subtrees to never be
60 generated (or merged, etc)
62 - Is there any way we can avoid creating a GSS.Node instance for
63 nodes which are transient in the sense that they have only one
66 - Re-read Rekers, particularly the stuff on optimal sharing
68 - Isolate the Element objects from Parse.Table/GSS so we can move
71 - consider allowing a Forest.Body to represent some other Tree whose
72 Body's should be [recursively] considered part of this Forest.
74 - perhaps not: right now we have a nice situation where
75 Forest.Ref instances become immutable once iterator()ed. This
76 also gives us a strong place to to culling with the certainty
77 that we won't throw out a Body which would later be salvaged
78 by some yet-to-be-added dependency.
80 - Figure out if there is a way to:
82 - allow unwrapping of children other than the very last one.
84 - fold repetitions into an array form in Forest, before
85 conversion to Tree. The major problem here is that multiple
86 tree-arrays are possible, all of different lengths. Worse,
87 even if they're all the same length, not all elements belong
88 in the same "possibility vector" as all others. You
89 essentially need a GSS to represent the array, which perhaps
90 is what the unfolded form was in the first place.
92 - Wikipedia grammar (needs to be both lexerless and boolean)
95 => Ordered Choice (";" operator)
97 - bring back in parse-table phase resolution of precedence (just
98 like associativity). This can be inferred from the use of ">"
99 when the rules are in one of these special forms:
110 where "_" is anything and "E" is the defining nonterminal.
111 Essentially what we're looking for is the situation where the
112 leftmost portion of one rule produces another rule, and the
113 rightmost portion of the latter produces the former.
115 I'm not 100% certain that this is as "strong" as the prefer/avoid
116 form (try to prove this, you probably can), but it's "what people
117 intend" most of the time.
119 - implement Johnstone's algorithm for "reduced, resolved LR
120 tables" to eliminate superfluous reductions on
123 ______________________________________________________________________________
126 - Rekers & Koorn note that GLR Substring Parsing can be used to do
127 really elegant and generalized "autocompletion".
130 ______________________________________________________________________________
133 - Incremental parse table construction
134 - "lazy GLR" and "lazy trees" -> language with first-class CF matching
135 - perhaps linear boolean grammars instead? (linear time, quad space)
136 - Forest parsing => chained parsers
137 - unification parsing, attributes, etc
139 - Take another stab at maximal-match? Nonterminal not-followed-by is
141 - Error recovery based on substring parsing