diff options
Diffstat (limited to '')
-rw-r--r-- | src/mds-kbdc/simplify-tree.c | 48 |
1 files changed, 28 insertions, 20 deletions
diff --git a/src/mds-kbdc/simplify-tree.c b/src/mds-kbdc/simplify-tree.c index a6b4247..b9a5d7a 100644 --- a/src/mds-kbdc/simplify-tree.c +++ b/src/mds-kbdc/simplify-tree.c @@ -381,8 +381,8 @@ static int simplify_map(mds_kbdc_tree_map_t* restrict tree) mds_kbdc_tree_t** here; mds_kbdc_tree_t* dup_sequence = NULL; mds_kbdc_tree_t* temp; - size_t argument_index = 0; - int redo = 0, saved_errno; + size_t argument_index; + int redo = 0, need_reelimination, saved_errno; /* Check for bad things in the result. */ for (argument = tree->result; argument; argument = argument->next) @@ -425,24 +425,32 @@ static int simplify_map(mds_kbdc_tree_map_t* restrict tree) /* Remove ‘.’:s. */ REMOVE_NOTHING(sequence); - /* Copy sequence. */ - fail_if ((dup_sequence = mds_kbdc_tree_dup(tree->sequence), dup_sequence == NULL)); - - /* Eliminate alterations, remember, unordered subsequences have - been simplified to alternations of ordered subsequences. */ - for (argument = dup_sequence; argument; argument = argument->next, argument_index++) - if (argument->type == C(ALTERNATION)) - fail_if (eliminate_alternation((mds_kbdc_tree_t*)tree, argument, argument_index)); - - mds_kbdc_tree_free(dup_sequence), dup_sequence = NULL; - - /* Eliminated ordered subsequences. */ - for (here = &(tree->sequence); (argument = *here); redo ? (redo = 0) : (here = &(argument->next), 0)) - if (argument->type == C(ORDERED)) - { - FLATTEN(argument); - redo = 1; - } + /* Because unordered are simplified to alternations of ordered subsequences, which + in turn can contain alternations, possibiled from simplification of nested + unordered sequenceses, we need to reeliminated until there are not alternations. */ + for (need_reelimination = 1; need_reelimination ? (need_reelimination = 0, 1) : 0; redo = 0) + { + /* Copy sequence. */ + fail_if ((dup_sequence = mds_kbdc_tree_dup(tree->sequence), dup_sequence == NULL)); + + /* Eliminate alterations, remember, unordered subsequences have + been simplified to alternations of ordered subsequences. */ + for (argument_index = 0, argument = dup_sequence; argument; argument = argument->next, argument_index++) + if (argument->type == C(ALTERNATION)) + fail_if (eliminate_alternation((mds_kbdc_tree_t*)tree, argument, argument_index)); + + mds_kbdc_tree_free(dup_sequence), dup_sequence = NULL; + + /* Eliminated ordered subsequences. */ + for (here = &(tree->sequence); (argument = *here); redo ? (redo = 0) : (here = &(argument->next), 0)) + if (argument->type == C(ORDERED)) + { + FLATTEN(argument); + redo = 1; + } + else if (argument->type == C(ALTERNATION)) + need_reelimination = 1; + } /* Valid value properties. */ if (tree->result == NULL) |