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desugaring done for many and attr_bool

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Meredith L. Patterson 2013-02-20 20:43:16 -05:00
parent 101e90ad9b
commit ab89b0fd4d
6 changed files with 70 additions and 15 deletions
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54
src/parsers/many.c
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@ -57,6 +57,60 @@ static bool many_isValidCF(void *env) {
}
static HCFChoice* desugar_many(HAllocator *mm__, void *env) {
HRepeat *repeat = (HRepeat*)env;
/* many(A) =>
Ma -> A Mar
-> \epsilon (but not if many1/sepBy1 is used)
Mar -> Sep A Mar
-> \epsilon
*/
HCFChoice *ret = h_new(HCFChoice, 1);
ret->type = HCF_CHOICE;
if (repeat->min_p)
ret->seq = h_new(HCFSequence*, 2); /* choice of 1 sequence, A Mar */
else
ret->seq = h_new(HCFSequence*, 3); /* choice of 2 sequences, A Mar | epsilon */
ret->seq[0] = h_new(HCFSequence, 1);
ret->seq[0]->items = h_new(HCFChoice*, 2);
/* create first subrule */
HCFChoice *ma = h_new(HCFChoice, 3);
ma->type = HCF_CHOICE;
ma->seq[0]->items[0] = repeat->p->vtable->desugar(mm__, repeat->p->env);
/* create second subrule */
HCFChoice *mar = h_new(HCFChoice, 3);
mar->type = HCF_CHOICE;
mar->seq = h_new(HCFSequence*, 2);
mar->seq[0] = h_new(HCFSequence, 1);
mar->seq[0]->items = h_new(HCFChoice*, 4);
mar->seq[0]->items[0] = repeat->sep->vtable->desugar(mm__, repeat->sep->env);
mar->seq[0]->items[1] = repeat->p->vtable->desugar(mm__, repeat->p->env);
mar->seq[0]->items[2] = mar; // woo recursion!
mar->seq[0]->items[3] = NULL;
mar->seq[1]->items = h_new(HCFChoice*, 2);
mar->seq[1]->items[0] = desugar_epsilon(mm__, NULL);\
mar->seq[1]->items[1] = NULL;
mar->seq[2]->items = NULL;
/* attach second subrule to first subrule */
ma->seq[0]->items[1] = mar;
ma->seq[0]->items[2] = NULL;
/* attach first subrule to ret */
ret->seq[0]->items[0] = ma;
ret->seq[0]->items[1] = NULL;
/* if not many1/sepBy1, attach epsilon */
if (repeat->min_p) {
ret->seq[1]->items = NULL;
} else {
ret->seq[1]->items = h_new(HCFChoice*, 2);
ret->seq[1]->items[0] = desugar_epsilon(mm__, NULL);
ret->seq[1]->items[1] = NULL;
ret->seq[2]->items = NULL;
}
return ret;
}
static const HParserVtable many_vt = {