// left OPERATOR right style expressions
// the most common form of expressions
// for things like 1 + 3
#region lValueOperatorrValueCalls
internal void genericExpVisitor(YarnSpinnerParser.ExpressionContext left, YarnSpinnerParser.ExpressionContext right, int op)
{
Visit(left);
Visit(right);
// TODO: temp operator call
compiler.Emit(ByteCode.CallFunc, tokens[op].ToString());
}
// operatorEquals style operators, eg +=
// these two should only be called during a SET operation
// eg << set $var += 1 >>
// the left expression has to be a variable
// the right value can be anything
#region operatorEqualsCalls
// generic helper for these types of expressions
internal void opEquals(string varName, YarnSpinnerParser.ExpressionContext expression, int op)
{
// Get the current value of the variable
compiler.Emit(ByteCode.PushVariable, varName);
// run the expression
Visit(expression);
// Stack now contains [currentValue, expressionValue]
// now we evaluate the operator
// op will match to one of + - / * %
compiler.Emit(ByteCode.CallFunc, tokens[op].ToString());
// Stack now has the destination value
// now store the variable and clean up the stack
compiler.Emit(ByteCode.StoreVariable, varName);
compiler.Emit(ByteCode.Pop);
}
internal void generateClause(string jumpLabel, YarnSpinnerParser.StatementContext[] children, YarnSpinnerParser.ExpressionContext expression)
{
string endOfClauseLabel = compiler.RegisterLabel("skipclause");
// handling the expression (if it has one)
// will only be called on ifs and elseifs
if (expression != null)
{
Visit(expression);
compiler.Emit(ByteCode.JumpIfFalse, endOfClauseLabel);
}
// running through all of the children statements
foreach (var child in children)
{
Visit(child);
}
compiler.Emit(ByteCode.JumpTo, jumpLabel);
if (expression != null)
{
compiler.Emit(ByteCode.Label, endOfClauseLabel);
compiler.Emit(ByteCode.Pop);
}
}
