Method CheckExpression

Common/Misc/vtkFunctionParser.cxx:1877–2164

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void vtkFunctionParser::CheckExpression(int& pos, char** error)
{
  if (this->FunctionMTime.GetMTime() > this->CheckMTime.GetMTime())
  {
    // Need to parse again.

    // Reset previous error cache.
    this->ParseErrorPositon = -1;
    this->SetParseError(nullptr);

    this->CopyParseError(pos, error);
  }
  else
  {
    this->CopyParseError(pos, error);
    return;
  }

  this->CheckMTime.Modified();

  this->RemoveSpaces();

  int index = 0, parenthesisCount = 0, currentChar;
  int functionNumber, constantNumber;
  int* expectCommaOnParenthesisCount = new int[this->FunctionLength];
  int* expectTwoCommasOnParenthesisCount = new int[this->FunctionLength];
  int i;

  for (i = 0; i < this->FunctionLength; i++)
  {
    expectCommaOnParenthesisCount[i] = 0;
    expectTwoCommasOnParenthesisCount[i] = 0;
  }

  while (true)
  {
    currentChar = this->Function[index];
    bool breakToOuterLoop = false;

    // Check for valid operand (must appear)

    // Check for leading -
    if (currentChar == '-')
    {
      currentChar = this->Function[++index];
      if (index == this->FunctionLength)
      {
        this->ParseErrorPositon = this->FindPositionInOriginalFunction(index);
        this->SetParseError("Syntax error: unary minus with no operand");
        this->CopyParseError(pos, error);
        delete[] expectCommaOnParenthesisCount;
        delete[] expectTwoCommasOnParenthesisCount;
        return;
      }
    }

    // Check for leading +
    if (currentChar == '+')