1 _____________________________________________________________________________
4 - Sensible tree-printout
5 - make Tib.Block extend Tree<>
7 - more natural phrasing of metagrammar?
9 - finalize metagrammar and rdp-op's
11 - Deal with the problem of zero-rep productions and whitespace insertion
13 - should Union.add() be there?
14 - should Atom.top() be there?
16 - fix the location stuff, it's broken
17 - decent/better error messages
18 - substring parsing required
24 - RFC2822 (email message/headers)
28 ______________________________________________________________________________
31 - clean up the whole Walk situation
34 - right now I can only lift the last child in a forest... begs
35 the question of what the right representation for Forests is
36 if we need to be able to do lift operations on it.
39 - "Regular Right Part" grammars (NP Chapman, etc)
40 - Attribute unification
42 - serialization of parse tables
43 - inference of rejections for literals
44 - "prefer whitespace higher up" (?)
45 - "ambiguity modulo dropped fragments"?
46 - can this be checked statically?
47 - eliminated statically?
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52 - Implement a k-token peek buffer (for each state, see if it "dead
53 ends" during the next k Phases based solely on state -- ignoring
56 - Arrange for the SPPF corresponding to dropped subtrees to never be
57 generated (or merged, etc)
59 - Is there any way we can avoid creating a GSS.Node instance for
60 nodes which are transient in the sense that they have only one
63 - Re-read Rekers, particularly the stuff on optimal sharing
65 - Isolate the Element objects from Parse.Table/GSS so we can move
68 - consider allowing a Forest.Body to represent some other Tree whose
69 Body's should be [recursively] considered part of this Forest.
71 - perhaps not: right now we have a nice situation where
72 Forest.Ref instances become immutable once iterator()ed. This
73 also gives us a strong place to to culling with the certainty
74 that we won't throw out a Body which would later be salvaged
75 by some yet-to-be-added dependency.
77 - Figure out if there is a way to:
79 - allow unwrapping of children other than the very last one.
81 - fold repetitions into an array form in Forest, before
82 conversion to Tree. The major problem here is that multiple
83 tree-arrays are possible, all of different lengths. Worse,
84 even if they're all the same length, not all elements belong
85 in the same "possibility vector" as all others. You
86 essentially need a GSS to represent the array, which perhaps
87 is what the unfolded form was in the first place.
89 - Wikipedia grammar (needs to be both lexerless and boolean)
92 => Ordered Choice (";" operator)
94 - bring back in parse-table phase resolution of precedence (just
95 like associativity). This can be inferred from the use of ">"
96 when the rules are in one of these special forms:
107 where "_" is anything and "E" is the defining nonterminal.
108 Essentially what we're looking for is the situation where the
109 leftmost portion of one rule produces another rule, and the
110 rightmost portion of the latter produces the former.
112 I'm not 100% certain that this is as "strong" as the prefer/avoid
113 form (try to prove this, you probably can), but it's "what people
114 intend" most of the time.
116 - implement Johnstone's algorithm for "reduced, resolved LR
117 tables" to eliminate superfluous reductions on
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123 - Rekers & Koorn note that GLR Substring Parsing can be used to do
124 really elegant and generalized "autocompletion".