private void Factor()
{
if (Stream.Accept(TokenType.Word, "print"))
{
TernaryExpression();
Instructions.Add(new Instruction(Opcode.Print));
}
else if (Stream.Accept(TokenType.Word, "len"))
{
TernaryExpression();
Instructions.Add(new Instruction(Opcode.GetVariableLength));
}
else if (Stream.Accept(TokenType.Word, "nil"))
{
Instructions.Add(new Instruction(Opcode.Push, new Variant()));
}
else if (Stream.Accept(TokenType.Delimiter, "("))
{
TernaryExpression();
Stream.Expect(TokenType.Delimiter, ")");
}
else if (Stream.Accept(TokenType.Delimiter, "["))
{
int varIndex = AddTempVariable();
ArrayDeclaration(varIndex);
Instructions.Add(new Instruction(Opcode.GetVariable, new Variant(varIndex)));
}
else if (Stream.Pass(TokenType.Word))
{
switch (Stream.PeekAhead(1).Value)
{
case "[":
{
Variant arrayVariable = new Variant(GetVariableIndex(Stream.GetWord()));
Stream.Expect(TokenType.Delimiter, "[");
Expression();
Stream.Expect(TokenType.Delimiter, "]");
Instructions.Add(new Instruction(Opcode.GetArrayVariable, arrayVariable));
break;
}
case "(":
MethodCall();
break;
default:
Instructions.Add(new Instruction(Opcode.GetVariable, new Variant(GetVariableIndex(Stream.GetWord()))));
break;
}
}
else if (Stream.Pass(TokenType.Number) || Stream.Pass(TokenType.String))
{
Instructions.Add(new Instruction(Opcode.Push, Stream.GetVariant()));
}
else if (!Parser.IsIncrementOperation(Stream.Peek()))
Stream.Expected("builtin function, variable or literal");
if (Stream.Accept(TokenType.Delimiter, "++"))
{
int variableIndex = GetVariableIndex(Stream.PeekAhead(-2).Value);
Instructions.Add(new Instruction(Opcode.IncrementVariable, new List<Variant> { new Variant(variableIndex), new Variant(1) }));
}
else if (Stream.Accept(TokenType.Delimiter, "--"))
{
int variableIndex = GetVariableIndex(Stream.PeekAhead(-2).Value);
Instructions.Add(new Instruction(Opcode.IncrementVariable, new List<Variant> { new Variant(variableIndex), new Variant(-1) }));
}
}
public Instruction(Opcode opcode, Variant operand)
{
Opcode = opcode;
Operands = new List<Variant> { operand };
}