1 _____________________________________________________________________________
4 - evil problems with: (x y? z /ws)
5 - it gets even more evil than that
9 - MUST HAVE BETTER ERROR MESSAGES
10 - when ambiguity encountered, show text region (where-to-where)
11 - use for developing java15.g
15 - topology no longer needed as an arg to parser
16 - expose parser's protected method?
18 - do Forest/Tree still need a Region?
22 ______________________________________________________________________________
25 - broader regression testing (for stuff like error messages, etc)
27 - More topology untangling [later]
28 - tib: use the lexer only for indentation increases/decreases
29 - grammar highlighting?
31 - Forest needs a "manual access" API
32 - the unwrap bit in Forest makes it really hard to expose an API for forests
36 ______________________________________________________________________________
39 - finalize metagrammar and rdp-op's
44 - RFC2822 (email message/headers)
45 - clean up the whole Walk situation (?)
48 ______________________________________________________________________________
51 - serialization of parse tables
53 - "ambiguity modulo dropped fragments"?
54 - can this be checked statically?
55 - eliminated statically?
57 - substring parsing for better error messages
60 - "Regular Right Part" grammars (NP Chapman, etc)
61 - Attribute unification
63 - inference of rejections for literals
64 - "prefer whitespace higher up" (?)
66 - Labeled edges on trees (associate a label with each slot in the
67 child array in Forest.Body? might make equality tough) --
68 equivalent to Feature Structures. Colon-labeling.
70 ______________________________________________________________________________
73 - Partly-Linear-PATR? (O(n^6) unification grammar)
75 - Implement a k-token peek buffer (for each state, see if it "dead
76 ends" during the next k Phases based solely on state -- ignoring
79 - Arrange for the SPPF corresponding to dropped subtrees to never be
80 generated (or merged, etc)
82 - Is there any way we can avoid creating a GSS.Node instance for
83 nodes which are transient in the sense that they have only one
86 - Re-read Rekers, particularly the stuff on optimal sharing
88 - Isolate the Element objects from Parse.Table/GSS so we can move
91 - consider allowing a Forest.Body to represent some other Tree whose
92 Body's should be [recursively] considered part of this Forest.
94 - perhaps not: right now we have a nice situation where
95 Forest.Ref instances become immutable once iterator()ed. This
96 also gives us a strong place to to culling with the certainty
97 that we won't throw out a Body which would later be salvaged
98 by some yet-to-be-added dependency.
100 - Figure out if there is a way to:
102 - allow unwrapping of children other than the very last one.
104 - fold repetitions into an array form in Forest, before
105 conversion to Tree. The major problem here is that multiple
106 tree-arrays are possible, all of different lengths. Worse,
107 even if they're all the same length, not all elements belong
108 in the same "possibility vector" as all others. You
109 essentially need a GSS to represent the array, which perhaps
110 is what the unfolded form was in the first place.
112 - Wikipedia grammar (needs to be both lexerless and boolean)
115 => Ordered Choice (";" operator)
117 - bring back in parse-table phase resolution of precedence (just
118 like associativity). This can be inferred from the use of ">"
119 when the rules are in one of these special forms:
130 where "_" is anything and "E" is the defining nonterminal.
131 Essentially what we're looking for is the situation where the
132 leftmost portion of one rule produces another rule, and the
133 rightmost portion of the latter produces the former.
135 I'm not 100% certain that this is as "strong" as the prefer/avoid
136 form (try to prove this, you probably can), but it's "what people
137 intend" most of the time.
139 - implement Johnstone's algorithm for "reduced, resolved LR
140 tables" to eliminate superfluous reductions on
143 ______________________________________________________________________________
146 - Rekers & Koorn note that GLR Substring Parsing can be used to do
147 really elegant and generalized "autocompletion".
150 ______________________________________________________________________________
153 - Incremental parse table construction
154 - "lazy GLR" and "lazy trees" -> language with first-class CF matching
155 - perhaps linear boolean grammars instead? (linear time, quad space)
156 - Forest parsing => chained parsers
157 - unification parsing, attributes, etc
159 - Take another stab at maximal-match? Nonterminal not-followed-by is
161 - Error recovery based on substring parsing