node UniqueStringN(char *s, unsigned int len){
int h = hashn(s,len) % numberof(hash_buckets);
node p;
for (p = hash_buckets[h]; p != NULL; p = CDR(p)) {
node q = CAR(p);
assertpos(q->tag == unique_string_tag,q);
if (strequaln(q->body.unique_string.characters,s,len)) {
return q;
}
}
node q = newnode(UNIQUE_STRING,unique_string_tag);
q->body.unique_string.characters = strnperm(s,len);
q->body.unique_string.hash = h;
push(hash_buckets[h],q);
return q;
}
node IntegerN(char *s, unsigned int len) {
node q = newnode(INT_CONST,int_const_tag);
q->body.int_const.contents = strnperm(s,len);
return q;
}
static node DoubleN(char *s, unsigned int len) {
node q = newnode(DOUBLE_CONST,double_const_tag);
q->body.double_const.contents = strnperm(s,len);
return q;
}
char *strperm(const char *s){
return strnperm(s,strlen(s));
}
node gettoken(){
char *p = cur.text;
if (*p == '\'') {
char c;
node token;
advance();
if (cur.text == cur.eot) {
fatal("file ends in character constant");
}
if (*cur.text == '\\') {
advance();
if (cur.text == cur.eot) {
fatal("file ends in character constant");
}
c = escaped(*cur.text);
}
else c = *cur.text;
advance();
if (cur.text == cur.eot) fatal("file ends in character constant");
if (*cur.text != '\'') {
fatal("character constant not terminated");
}
advance();
token = newnode (CHAR_CONST,char_const_tag);
token->body.char_const.contents = c;
return token;
}
if (*p == '"') {
char *s;
node token;
advance();
s = cur.text;
while (TRUE) {
if (cur.text == cur.eot) fatal("file ends before string");
if (cur.text[0]=='"') break;
if (*cur.text == '\\') {
advance();
if (cur.text == cur.eot) fatal("file ends before string");
}
advance();
}
token = newnode(STRING_CONST,string_const_tag);
token->body.unique_string.characters = strnperm(s,cur.text-s); /* observe that escaped character sequences such as \n are not simplified here */
advance();
return token;
}
if (*p == ',' || *p == '.') {
advance();
}
else {
bool digitssofar = TRUE;
while (TRUE) {
if (!isdigit((int)*cur.text)) digitssofar = FALSE;
advance();
if (cur.text == cur.eot) break;
if (*cur.text == '.' && digitssofar) continue;
if (istoken(*cur.text)) continue;
break;
}
if (integerq(p,cur.text-p)) {
return IntegerN(p,cur.text-p);
}
if (doubleq(p,cur.text-p)) {
return DoubleN(p,cur.text-p);
}
}
return UniqueStringN(p,cur.text-p);
}
