void h_seq_snoc(HParsedToken *xs, const HParsedToken *x)
{
assert(xs != NULL);
assert(xs->token_type == TT_SEQUENCE);
h_carray_append(xs->seq, (HParsedToken *)x);
}
void h_seq_append(HParsedToken *xs, const HParsedToken *ys)
{
assert(xs != NULL);
assert(xs->token_type == TT_SEQUENCE);
assert(ys != NULL);
assert(ys->token_type == TT_SEQUENCE);
for(size_t i=0; i<ys->seq->used; i++)
h_carray_append(xs->seq, ys->seq->elements[i]);
}
static void act_flatten_(HCountedArray *seq, const HParsedToken *tok) {
if(tok == NULL) {
return;
} else if(tok->token_type == TT_SEQUENCE) {
size_t i;
for(i=0; i<tok->seq->used; i++)
act_flatten_(seq, tok->seq->elements[i]);
} else {
h_carray_append(seq, (HParsedToken *)tok);
}
}
static HParseResult* parse_sequence(void *env, HParseState *state) {
HSequence *s = (HSequence*)env;
HCountedArray *seq = h_carray_new_sized(state->arena, (s->len > 0) ? s->len : 4);
for (size_t i=0; i<s->len; ++i) {
HParseResult *tmp = h_do_parse(s->p_array[i], state);
// if the interim parse fails, the whole thing fails
if (NULL == tmp) {
return NULL;
} else {
if (tmp->ast)
h_carray_append(seq, (void*)tmp->ast);
}
}
HParsedToken *tok = a_new(HParsedToken, 1);
tok->token_type = TT_SEQUENCE; tok->seq = seq;
return make_result(state->arena, tok);
}
static HParsedToken *reshape_sequence(const HParseResult *p) {
assert(p->ast);
assert(p->ast->token_type == TT_SEQUENCE);
HCountedArray *seq = h_carray_new(p->arena);
// drop all elements that are NULL
for(size_t i=0; i<p->ast->seq->used; i++) {
if(p->ast->seq->elements[i] != NULL)
h_carray_append(seq, p->ast->seq->elements[i]);
}
HParsedToken *res = a_new_(p->arena, HParsedToken, 1);
res->token_type = TT_SEQUENCE;
res->seq = seq;
res->index = p->ast->index;
res->bit_offset = p->ast->bit_offset;
return res;
}
static HParseResult *parse_many(void* env, HParseState *state) {
HRepeat *env_ = (HRepeat*) env;
HCountedArray *seq = h_carray_new_sized(state->arena, (env_->count > 0 ? env_->count : 4));
size_t count = 0;
HInputStream bak;
while (env_->min_p || env_->count > count) {
bak = state->input_stream;
if (count > 0) {
HParseResult *sep = h_do_parse(env_->sep, state);
if (!sep)
goto err0;
}
HParseResult *elem = h_do_parse(env_->p, state);
if (!elem)
goto err0;
if (elem->ast)
h_carray_append(seq, (void*)elem->ast);
count++;
}
if (count < env_->count)
goto err;
succ:
; // necessary for the label to be here...
HParsedToken *res = a_new(HParsedToken, 1);
res->token_type = TT_SEQUENCE;
res->seq = seq;
return make_result(state, res);
err0:
if (count >= env_->count) {
state->input_stream = bak;
goto succ;
}
err:
state->input_stream = bak;
return NULL;
}
