From ab89b0fd4d0c6a1a876513754fe6d8a9d15eefe6 Mon Sep 17 00:00:00 2001
From: "Meredith L. Patterson" <mlp@thesmartpolitenerd.com>
Date: Wed, 20 Feb 2013 20:43:16 -0500
Subject: [PATCH] desugaring done for many and attr_bool

---
 src/internal.h                |  1 +
 src/parsers/attr_bool.c       |  3 +-
 src/parsers/epsilon.c         | 13 ---------
 src/parsers/int_range.c       |  1 +
 src/parsers/many.c            | 54 +++++++++++++++++++++++++++++++++++
 src/parsers/parser_internal.h | 13 +++++++++
 6 files changed, 70 insertions(+), 15 deletions(-)

diff --git a/src/internal.h b/src/internal.h
index 7e03657..279f998 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -257,6 +257,7 @@ typedef struct HCFChoice_ {
     uint8_t chr;
   };
   HAction action;
+  HPredicate pred;
 } HCFChoice;
 
 struct HCFSequence_ {
diff --git a/src/parsers/attr_bool.c b/src/parsers/attr_bool.c
index 46f511f..9e69ebe 100644
--- a/src/parsers/attr_bool.c
+++ b/src/parsers/attr_bool.c
@@ -43,8 +43,7 @@ static HCFChoice* desugar_ab(HAllocator *mm__, void *env) {
   ret->seq = h_new(HCFSequence*, 2);
   ret->seq[0] = seq;
   ret->seq[1] = NULL;
-  /* TODO: need to process this as an HPredicate */
-  ret->action = a->action;
+  ret->pred = a->pred;
   return ret;
 }
 
diff --git a/src/parsers/epsilon.c b/src/parsers/epsilon.c
index d802246..ffb47d1 100644
--- a/src/parsers/epsilon.c
+++ b/src/parsers/epsilon.c
@@ -8,19 +8,6 @@ static HParseResult* parse_epsilon(void* env, HParseState* state) {
   return res;
 }
 
-static HCFChoice* desugar_epsilon(HAllocator *mm__, void *env) {
-  static HCFChoice *res_seq_l[] = {NULL};
-  static HCFSequence res_seq = {res_seq_l};
-  static HCFSequence *res_ch_l[] = {&res_seq, NULL};
-  static HCFChoice res_ch = {
-    .type = HCF_CHOICE,
-    .seq = res_ch_l,
-    .action = NULL
-  };
-
-  return &res_ch;
-}
-
 static const HParserVtable epsilon_vt = {
   .parse = parse_epsilon,
   .isValidRegular = h_true,
diff --git a/src/parsers/int_range.c b/src/parsers/int_range.c
index f2ee03f..64450da 100644
--- a/src/parsers/int_range.c
+++ b/src/parsers/int_range.c
@@ -29,6 +29,7 @@ static HParseResult* parse_int_range(void *env, HParseState *state) {
 }
 
 HCFChoice* gen_int_range(HAllocator *mm__, uint64_t low, uint64_t high, uint8_t bytes) {
+  /* Possible FIXME: TallerThanMe */
   if (1 == bytes) {
     HCFChoice *cs = h_new(HCFChoice, 1);
     cs->type = HCF_CHARSET;
diff --git a/src/parsers/many.c b/src/parsers/many.c
index 15f020b..7ea63d9 100644
--- a/src/parsers/many.c
+++ b/src/parsers/many.c
@@ -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 = {
diff --git a/src/parsers/parser_internal.h b/src/parsers/parser_internal.h
index d966ecc..7e5bb06 100644
--- a/src/parsers/parser_internal.h
+++ b/src/parsers/parser_internal.h
@@ -26,4 +26,17 @@ static inline size_t token_length(HParseResult *pr) {
 static inline bool h_true(void *env) { return true; }
 static inline bool h_false(void *env) { return false; }
 
+/* Epsilon rules happen during desugaring. This handles them. */
+static inline HCFChoice* desugar_epsilon(HAllocator *mm__, void *env) {
+  static HCFChoice *res_seq_l[] = {NULL};
+  static HCFSequence res_seq = {res_seq_l};
+  static HCFSequence *res_ch_l[] = {&res_seq, NULL};
+  static HCFChoice res_ch = {
+    .type = HCF_CHOICE,
+    .seq = res_ch_l,
+    .action = NULL
+  };
+  return &res_ch;
+}
+
 #endif // HAMMER_PARSE_INTERNAL__H