Max Brunsfeld
43ae8235fd
Remove the error action; a lack of actions implies an error.
2016-06-21 22:53:48 -07:00
Max Brunsfeld
6a7a5cfc3f
Remove nesting in parse action struct
2016-06-21 21:36:33 -07:00
Max Brunsfeld
634ee29d10
Clean up main consume_lookahead loop
2016-06-21 21:27:33 -07:00
Max Brunsfeld
38c144b4a3
Refine logic for deciding when tokens need to be re-lexed
...
* While generating the lex table, note which tokens can match the
same string. A token needs to be relexed when it has possible
homonyms in the current state.
* Also note which tokens can match substrings of each other tokens.
A token needs to be relexed when there are viable tokens that
could match longer strings in the current state and the next
token has been edited.
* Remove the logic for marking tokens as fragile on creation.
* Store the reusability/non-reusability of symbols off of individual
actions and onto the entire entry for the state & symbol.
2016-06-21 07:28:04 -07:00
Max Brunsfeld
94721c7ec0
Rewind and re-tokenize in error mode after detecting an error
2016-06-17 21:26:03 -07:00
Max Brunsfeld
e70547cd11
Allow recoveries that skip leading children of invisible trees
...
Before this, errors could only be recovered by skipping internal children.
2016-06-14 14:48:35 -07:00
Max Brunsfeld
f77c08eff5
Check for better stack versions earlier when handling errors
2016-06-12 17:41:25 -07:00
Max Brunsfeld
ef2c3a10e3
Fix bug when reusing formerly extra trees as non-extra trees
2016-06-12 17:26:15 -07:00
Max Brunsfeld
e1c51556f2
Check that error repair reductions have the right child count
...
Also, avoid repetitively walking through the parse table to verify the
child trees in an error repair. Instead, walk through the parse table
once, and reuse the list of reductions that would be valid after that
sequence.
2016-06-10 13:15:45 -07:00
Max Brunsfeld
00a0939504
Abort erroneous parse versions more eagerly
2016-06-02 14:04:48 -07:00
Max Brunsfeld
96e2e49ef8
Fix false positive when marking nodes unreusable due to ambiguity
2016-05-30 14:16:55 -07:00
Max Brunsfeld
ea47fdc0fe
Rework logic for when to abandon parses with errors
2016-05-29 22:36:47 -07:00
Max Brunsfeld
6535704870
Replace stack_merge_new function with two simpler functions
...
- merge(version1, version2)
- split(version)
2016-05-28 21:22:10 -07:00
Max Brunsfeld
e686478ad2
Rename stack_merge function to stack_merge_all
2016-05-28 20:24:08 -07:00
Max Brunsfeld
1e353381ff
Don't create error node in lexer unless token is completely invalid
...
Before, any syntax error would cause the lexer to create an error
leaf node. This could happen even with a valid input, if the parse
stack had split and one particular version of the parse stack
failed to parse.
Now, an error leaf node is only created when the lexer cannot understand
part of the input stream at all. When a normal syntax error occurs,
the lexer just returns a token that is outside of the expected token
set, and the parser handles the unexpected token.
2016-05-26 14:15:10 -07:00
Max Brunsfeld
77e0e4bb16
Fix some leaks after allocation failures occur
2016-05-16 10:53:31 -07:00
Max Brunsfeld
d50f6a58cc
Abort parse versions w/ worse errors when repairing an error
2016-05-16 10:33:19 -07:00
Max Brunsfeld
22c550c9d6
Discard tokens after error detection to find the best repair
...
* Use GLR stack-splitting to try all numbers of tokens to
discard until a repair is found.
* Check the validity of repairs by looking at the child trees,
rather than the statically-computed 'in-progress symbols' list
2016-05-11 13:49:43 -07:00
Max Brunsfeld
31f6b2e24a
Refactor construction of out-of-context states
2016-04-25 21:59:40 -07:00
Max Brunsfeld
e99a3925e0
Merge all versions created in a given reduce operation
2016-04-24 00:55:19 -07:00
Max Brunsfeld
fd4c33209e
Select ambiguous alternatives by minimizing error size
2016-04-24 00:54:20 -07:00
Max Brunsfeld
0ea2962fbe
Clean up consume_lookahead function
2016-04-18 11:17:07 -07:00
Max Brunsfeld
2f81a6f6c7
Don't recover from errors based on extra tokens
2016-04-15 23:14:31 -07:00
Max Brunsfeld
cad663b144
Consider multiple error repairs on the same path of the stack
...
This changes the API to the stack_iterate function so that you can pop
from the stack without stopping iteration
2016-04-15 21:28:00 -07:00
Max Brunsfeld
695be5bc79
Merge equivalent stacks in a separate stage of parsing
...
* No more automatic merging every time a state is pushed to the stack
* When popping from the stack, the current version is always preserved
2016-04-10 14:12:24 -07:00
Max Brunsfeld
827573f1c7
Clean up reduce function
2016-04-07 10:40:33 -07:00
Max Brunsfeld
5ba40f15ad
Rename stack heads to versions
2016-04-04 12:25:57 -07:00
Max Brunsfeld
2f3e92c9be
Add function for popping all nodes from the stack
2016-04-04 11:44:45 -07:00
Max Brunsfeld
267092940d
Collapse redundant interior error nodes
2016-04-03 23:46:43 -07:00
Max Brunsfeld
91e3609fbf
Write to file directly from stack debugging function
2016-04-02 22:18:44 -07:00
Max Brunsfeld
d5c4dacb35
Clean up parser.c
2016-04-02 20:58:27 -07:00
Max Brunsfeld
956b3e68d7
Only store one reusable node, not one for each stack version
2016-04-01 21:17:23 -07:00
Max Brunsfeld
6bce6da1e6
Store verifying flag within parse stack
2016-03-31 12:03:21 -07:00
Max Brunsfeld
07625808d3
Look for two consecutive valid tokens before resuming parsing after errors
2016-03-10 11:57:33 -08:00
Max Brunsfeld
a948cb3ea0
Allow normal reductions that pop to the initial error state
2016-03-10 11:56:10 -08:00
Max Brunsfeld
e7d3d40a59
Explicitly inform stack pop callback when the stack is exhausted
...
Also, pass non-extra tree count as a single value, rather than keeping
track of the extra count and the total separately.
2016-03-10 11:51:55 -08:00
Max Brunsfeld
288a164823
Retrieve current lookahead state before it can be removed in reduce
2016-03-10 11:44:23 -08:00
Max Brunsfeld
da4a3f6516
Don't abort on allocation failures while finishing parse
2016-03-10 11:42:10 -08:00
Max Brunsfeld
2e35587161
Use new stack_pop_until function for repairing errors
2016-03-07 20:06:46 -08:00
Max Brunsfeld
c0595c21c5
Halt stack pops at all error states, not just error trees
2016-03-03 11:05:37 -08:00
Max Brunsfeld
5f9be9d9b2
Make Failure enumerators have the value zero
2016-03-03 10:24:12 -08:00
Max Brunsfeld
c1fa1efaad
Give ParseActionResult enumerators more consistent names
2016-03-03 10:21:57 -08:00
Max Brunsfeld
3d516aeeec
Give StackPushResult enumerators shorter names
2016-03-03 10:20:05 -08:00
Max Brunsfeld
8a13b5d120
Rename StackPopResult -> StackSlice
2016-03-03 10:16:10 -08:00
Max Brunsfeld
b99db66ce7
Improve log message for handling errors
2016-03-03 09:37:37 -08:00
Max Brunsfeld
aef7582a2a
Start using the forward move to recover from errors
...
Some unit tests passing. Corpus tests still failing
2016-03-02 21:08:42 -08:00
Max Brunsfeld
e0c24e3be6
Remove old error recovery code
2016-03-02 20:58:39 -08:00
Max Brunsfeld
5a34d74702
Clean up stack
2016-02-25 21:51:39 -08:00
Max Brunsfeld
da2ef7ad35
Store trees in the links between stack nodes, not in the nodes themselves
2016-02-23 17:35:50 -08:00
Max Brunsfeld
abbc282950
Add a public function for printing debugging graphs
2016-02-23 11:16:50 -08:00
