int VisualScriptBuiltinFunc::get_input_value_port_count() const {
return get_func_argument_count(func);
}
Expression::ENode *Expression::_parse_expression() {
Vector<ExpressionNode> expression;
while (true) {
//keep appending stuff to expression
ENode *expr = NULL;
Token tk;
_get_token(tk);
if (error_set)
return NULL;
switch (tk.type) {
case TK_CURLY_BRACKET_OPEN: {
//a dictionary
DictionaryNode *dn = alloc_node<DictionaryNode>();
while (true) {
int cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_CURLY_BRACKET_CLOSE) {
break;
}
str_ofs = cofs; //revert
//parse an expression
ENode *subexpr = _parse_expression();
if (!subexpr)
return NULL;
dn->dict.push_back(subexpr);
_get_token(tk);
if (tk.type != TK_COLON) {
_set_error("Expected ':'");
return NULL;
}
subexpr = _parse_expression();
if (!subexpr)
return NULL;
dn->dict.push_back(subexpr);
cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_COMMA) {
//all good
} else if (tk.type == TK_CURLY_BRACKET_CLOSE) {
str_ofs = cofs;
} else {
_set_error("Expected ',' or '}'");
}
}
expr = dn;
} break;
case TK_BRACKET_OPEN: {
//an array
ArrayNode *an = alloc_node<ArrayNode>();
while (true) {
int cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_BRACKET_CLOSE) {
break;
}
str_ofs = cofs; //revert
//parse an expression
ENode *subexpr = _parse_expression();
if (!subexpr)
return NULL;
an->array.push_back(subexpr);
cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_COMMA) {
//all good
} else if (tk.type == TK_BRACKET_CLOSE) {
str_ofs = cofs;
} else {
_set_error("Expected ',' or ']'");
}
}
expr = an;
} break;
case TK_PARENTHESIS_OPEN: {
//a suexpression
ENode *e = _parse_expression();
if (error_set)
return NULL;
_get_token(tk);
if (tk.type != TK_PARENTHESIS_CLOSE) {
_set_error("Expected ')'");
return NULL;
}
expr = e;
} break;
case TK_IDENTIFIER: {
String identifier = tk.value;
int cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_PARENTHESIS_OPEN) {
//function call
CallNode *func_call = alloc_node<CallNode>();
func_call->method = identifier;
SelfNode *self_node = alloc_node<SelfNode>();
func_call->base = self_node;
while (true) {
int cofs2 = str_ofs;
_get_token(tk);
if (tk.type == TK_PARENTHESIS_CLOSE) {
break;
}
str_ofs = cofs2; //revert
//parse an expression
ENode *subexpr = _parse_expression();
if (!subexpr)
return NULL;
func_call->arguments.push_back(subexpr);
cofs2 = str_ofs;
_get_token(tk);
if (tk.type == TK_COMMA) {
//all good
} else if (tk.type == TK_PARENTHESIS_CLOSE) {
str_ofs = cofs2;
} else {
_set_error("Expected ',' or ')'");
}
}
expr = func_call;
} else {
//named indexing
str_ofs = cofs;
int input_index = -1;
for (int i = 0; i < input_names.size(); i++) {
if (input_names[i] == identifier) {
input_index = i;
break;
}
}
if (input_index != -1) {
InputNode *input = alloc_node<InputNode>();
input->index = input_index;
expr = input;
} else {
NamedIndexNode *index = alloc_node<NamedIndexNode>();
SelfNode *self_node = alloc_node<SelfNode>();
index->base = self_node;
index->name = identifier;
expr = index;
}
}
} break;
case TK_INPUT: {
InputNode *input = alloc_node<InputNode>();
input->index = tk.value;
expr = input;
} break;
case TK_SELF: {
SelfNode *self = alloc_node<SelfNode>();
expr = self;
} break;
case TK_CONSTANT: {
ConstantNode *constant = alloc_node<ConstantNode>();
constant->value = tk.value;
expr = constant;
} break;
case TK_BASIC_TYPE: {
//constructor..
Variant::Type bt = Variant::Type(int(tk.value));
_get_token(tk);
if (tk.type != TK_PARENTHESIS_OPEN) {
_set_error("Expected '('");
return NULL;
}
ConstructorNode *constructor = alloc_node<ConstructorNode>();
constructor->data_type = bt;
while (true) {
int cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_PARENTHESIS_CLOSE) {
break;
}
str_ofs = cofs; //revert
//parse an expression
ENode *subexpr = _parse_expression();
if (!subexpr)
return NULL;
constructor->arguments.push_back(subexpr);
cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_COMMA) {
//all good
} else if (tk.type == TK_PARENTHESIS_CLOSE) {
str_ofs = cofs;
} else {
_set_error("Expected ',' or ')'");
}
}
expr = constructor;
} break;
case TK_BUILTIN_FUNC: {
//builtin function
_get_token(tk);
if (tk.type != TK_PARENTHESIS_OPEN) {
_set_error("Expected '('");
return NULL;
}
BuiltinFuncNode *bifunc = alloc_node<BuiltinFuncNode>();
bifunc->func = BuiltinFunc(int(tk.value));
while (true) {
int cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_PARENTHESIS_CLOSE) {
break;
}
str_ofs = cofs; //revert
//parse an expression
ENode *subexpr = _parse_expression();
if (!subexpr)
return NULL;
bifunc->arguments.push_back(subexpr);
cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_COMMA) {
//all good
} else if (tk.type == TK_PARENTHESIS_CLOSE) {
str_ofs = cofs;
} else {
_set_error("Expected ',' or ')'");
}
}
int expected_args = get_func_argument_count(bifunc->func);
if (bifunc->arguments.size() != expected_args) {
_set_error("Builtin func '" + get_func_name(bifunc->func) + "' expects " + itos(expected_args) + " arguments.");
}
expr = bifunc;
} break;
case TK_OP_SUB: {
ExpressionNode e;
e.is_op = true;
e.op = Variant::OP_NEGATE;
expression.push_back(e);
continue;
} break;
case TK_OP_NOT: {
ExpressionNode e;
e.is_op = true;
e.op = Variant::OP_NOT;
expression.push_back(e);
continue;
} break;
default: {
_set_error("Expected expression.");
return NULL;
} break;
}
//before going to operators, must check indexing!
while (true) {
int cofs2 = str_ofs;
_get_token(tk);
if (error_set)
return NULL;
bool done = false;
switch (tk.type) {
case TK_BRACKET_OPEN: {
//value indexing
IndexNode *index = alloc_node<IndexNode>();
index->base = expr;
ENode *what = _parse_expression();
if (!what)
return NULL;
index->index = what;
_get_token(tk);
if (tk.type != TK_BRACKET_CLOSE) {
_set_error("Expected ']' at end of index.");
return NULL;
}
expr = index;
} break;
case TK_PERIOD: {
//named indexing or function call
_get_token(tk);
if (tk.type != TK_IDENTIFIER) {
_set_error("Expected identifier after '.'");
return NULL;
}
StringName identifier = tk.value;
int cofs = str_ofs;
_get_token(tk);
if (tk.type == TK_PARENTHESIS_OPEN) {
//function call
CallNode *func_call = alloc_node<CallNode>();
func_call->method = identifier;
func_call->base = expr;
while (true) {
int cofs3 = str_ofs;
_get_token(tk);
if (tk.type == TK_PARENTHESIS_CLOSE) {
break;
}
str_ofs = cofs3; //revert
//parse an expression
ENode *subexpr = _parse_expression();
if (!subexpr)
return NULL;
func_call->arguments.push_back(subexpr);
cofs3 = str_ofs;
_get_token(tk);
if (tk.type == TK_COMMA) {
//all good
} else if (tk.type == TK_PARENTHESIS_CLOSE) {
str_ofs = cofs3;
} else {
_set_error("Expected ',' or ')'");
}
}
expr = func_call;
} else {
//named indexing
str_ofs = cofs;
NamedIndexNode *index = alloc_node<NamedIndexNode>();
index->base = expr;
index->name = identifier;
expr = index;
}
} break;
default: {
str_ofs = cofs2;
done = true;
} break;
}
if (done)
break;
}
//push expression
{
ExpressionNode e;
e.is_op = false;
e.node = expr;
expression.push_back(e);
}
//ok finally look for an operator
int cofs = str_ofs;
_get_token(tk);
if (error_set)
return NULL;
Variant::Operator op = Variant::OP_MAX;
switch (tk.type) {
case TK_OP_IN: op = Variant::OP_IN; break;
case TK_OP_EQUAL: op = Variant::OP_EQUAL; break;
case TK_OP_NOT_EQUAL: op = Variant::OP_NOT_EQUAL; break;
case TK_OP_LESS: op = Variant::OP_LESS; break;
case TK_OP_LESS_EQUAL: op = Variant::OP_LESS_EQUAL; break;
case TK_OP_GREATER: op = Variant::OP_GREATER; break;
case TK_OP_GREATER_EQUAL: op = Variant::OP_GREATER_EQUAL; break;
case TK_OP_AND: op = Variant::OP_AND; break;
case TK_OP_OR: op = Variant::OP_OR; break;
case TK_OP_NOT: op = Variant::OP_NOT; break;
case TK_OP_ADD: op = Variant::OP_ADD; break;
case TK_OP_SUB: op = Variant::OP_SUBTRACT; break;
case TK_OP_MUL: op = Variant::OP_MULTIPLY; break;
case TK_OP_DIV: op = Variant::OP_DIVIDE; break;
case TK_OP_MOD: op = Variant::OP_MODULE; break;
case TK_OP_SHIFT_LEFT: op = Variant::OP_SHIFT_LEFT; break;
case TK_OP_SHIFT_RIGHT: op = Variant::OP_SHIFT_RIGHT; break;
case TK_OP_BIT_AND: op = Variant::OP_BIT_AND; break;
case TK_OP_BIT_OR: op = Variant::OP_BIT_OR; break;
case TK_OP_BIT_XOR: op = Variant::OP_BIT_XOR; break;
case TK_OP_BIT_INVERT: op = Variant::OP_BIT_NEGATE; break;
default: {};
}
if (op == Variant::OP_MAX) { //stop appending stuff
str_ofs = cofs;
break;
}
//push operator and go on
{
ExpressionNode e;
e.is_op = true;
e.op = op;
expression.push_back(e);
}
}
/* Reduce the set set of expressions and place them in an operator tree, respecting precedence */
while (expression.size() > 1) {
int next_op = -1;
int min_priority = 0xFFFFF;
bool is_unary = false;
for (int i = 0; i < expression.size(); i++) {
if (!expression[i].is_op) {
continue;
}
int priority;
bool unary = false;
switch (expression[i].op) {
case Variant::OP_BIT_NEGATE:
priority = 0;
unary = true;
break;
case Variant::OP_NEGATE:
priority = 1;
unary = true;
break;
case Variant::OP_MULTIPLY: priority = 2; break;
case Variant::OP_DIVIDE: priority = 2; break;
case Variant::OP_MODULE: priority = 2; break;
case Variant::OP_ADD: priority = 3; break;
case Variant::OP_SUBTRACT: priority = 3; break;
case Variant::OP_SHIFT_LEFT: priority = 4; break;
case Variant::OP_SHIFT_RIGHT: priority = 4; break;
case Variant::OP_BIT_AND: priority = 5; break;
case Variant::OP_BIT_XOR: priority = 6; break;
case Variant::OP_BIT_OR: priority = 7; break;
case Variant::OP_LESS: priority = 8; break;
case Variant::OP_LESS_EQUAL: priority = 8; break;
case Variant::OP_GREATER: priority = 8; break;
case Variant::OP_GREATER_EQUAL: priority = 8; break;
case Variant::OP_EQUAL: priority = 8; break;
case Variant::OP_NOT_EQUAL: priority = 8; break;
case Variant::OP_IN: priority = 10; break;
case Variant::OP_NOT:
priority = 11;
unary = true;
break;
case Variant::OP_AND: priority = 12; break;
case Variant::OP_OR: priority = 13; break;
default: {
_set_error("Parser bug, invalid operator in expression: " + itos(expression[i].op));
return NULL;
}
}
if (priority < min_priority) {
// < is used for left to right (default)
// <= is used for right to left
next_op = i;
min_priority = priority;
is_unary = unary;
}
}
if (next_op == -1) {
_set_error("Yet another parser bug....");
ERR_FAIL_COND_V(next_op == -1, NULL);
}
// OK! create operator..
if (is_unary) {
int expr_pos = next_op;
while (expression[expr_pos].is_op) {
expr_pos++;
if (expr_pos == expression.size()) {
//can happen..
_set_error("Unexpected end of expression...");
return NULL;
}
}
//consecutively do unary opeators
for (int i = expr_pos - 1; i >= next_op; i--) {
OperatorNode *op = alloc_node<OperatorNode>();
op->op = expression[i].op;
op->nodes[0] = expression[i + 1].node;
op->nodes[1] = NULL;
expression.write[i].is_op = false;
expression.write[i].node = op;
expression.remove(i + 1);
}
} else {
if (next_op < 1 || next_op >= (expression.size() - 1)) {
_set_error("Parser bug...");
ERR_FAIL_V(NULL);
}
OperatorNode *op = alloc_node<OperatorNode>();
op->op = expression[next_op].op;
if (expression[next_op - 1].is_op) {
_set_error("Parser bug...");
ERR_FAIL_V(NULL);
}
if (expression[next_op + 1].is_op) {
// this is not invalid and can really appear
// but it becomes invalid anyway because no binary op
// can be followed by a unary op in a valid combination,
// due to how precedence works, unaries will always disappear first
_set_error("Unexpected two consecutive operators.");
return NULL;
}
op->nodes[0] = expression[next_op - 1].node; //expression goes as left
op->nodes[1] = expression[next_op + 1].node; //next expression goes as right
//replace all 3 nodes by this operator and make it an expression
expression.write[next_op - 1].node = op;
expression.remove(next_op);
expression.remove(next_op);
}
}
return expression[0].node;
}
