KFormula* KFormula::parseKFormula(const char* str) {
if (!str || !*str) return NULL;
KFormula* ret = parseEQU(str);
while(isspace(*str)) ++str;
if (*str) { std::cerr << "ERROR: \""<< *str << "\"" << std::endl;}
assert(! *str);
return ret;
}
KFormula* KFormula::parseEQU(const char*& str) {
KFormula* left = parseIMP(str);
while(isspace(*str)) ++str;
if(strncmp(str,"<=>",3) == 0) {
// This is an equivalence
str += 3;
KFormula* right = parseEQU(str);
return new KFormula(KFormula::EQU,left,right);
} else {
return left;
// This is not an equivalence
}
}
KFormula* KFormula::parseRest(const char*& str) {
while(isspace(*str)) ++str;
KFormula *left;
if(*str == '('){
++str;
left = parseEQU(str);
while(isspace(*str)) ++str;
assert(*str == ')');
++str;
return left;
} else if (strncmp(str,"<", 1) == 0 && (isalnum(*(str + 1)) || *(str+1) == '-')) {
size_t n = 1;// "<"
if (*(str+1) == '-') ++n;
while(isalnum(*(str+n))) ++n;
std::string roleString(str+1, n - 1);
++n;// ">"
str += n;
left = parseRest(str);
left = new KFormula(KFormula::DIA,left,NULL);
left->setprop(roleString);
return left;
} else if (strncmp(str,"<>", 2) == 0) {
str += 2;
left = parseRest(str);
left = new KFormula(KFormula::DIA,left,NULL);
return left;
} else if (strncmp(str,"[", 1) == 0 && (isalnum(*(str + 1)) || *(str+1) == '-')) {
size_t n = 1;// "["
if (*(str+1) == '-') ++n;
while(isalnum(*(str+n))) ++n;
std::string roleString(str+1, n - 1);
++n;// "]"
str += n;
left = parseRest(str);
left = new KFormula(KFormula::BOX,left,NULL);
left->setprop(roleString);
return left;
}else if (strncmp(str,"[]",2) == 0) {
str += 2;
left = parseRest(str);
left = new KFormula(KFormula::BOX,left,NULL);
return left;
} else if (*str=='~') {
++str;
left = parseRest(str);
left = new KFormula(KFormula::NOT,left,NULL);
return left;
} else if (strncmp(str,"True",4)==0) {
str += 4;
return new KFormula(true);
} else if (strncmp(str,"False",5)==0) {
str += 5;
return new KFormula(false);
} else if (isalpha(*str) || *str == '_') {
size_t n = 1;
while(isalnum(*(str+n)) || *(str+n) == '_') ++n;
left = new KFormula(std::string(str,n));
str += n;
return left;
}
assert(false && "Could not parse input");
// Must not reach here
}
