public void GetAsDigit()
{
CharBuffer buffer = CharBuffer.FromString("c1");
Assert.IsFalse(buffer.NextIsDigit());
Assert.AreEqual(buffer.Get(), 'c');
Assert.IsTrue(buffer.NextIsDigit());
Assert.AreEqual(buffer.GetAsDigit(), 1);
Assert.IsFalse(buffer.NextIsDigit());
}
/// <summary>
/// Internal method for parsing charge, to allow concatenated signs (--, ++)
/// the method recursively invokes increment or decrementing an accumulator.
/// </summary>
/// <param name="acc"> accumulator</param>
/// <param name="buffer">a character buffer</param>
/// <returns>the charge value</returns>
private static int ReadCharge(int acc, CharBuffer buffer)
{
if (buffer.GetIf('+'))
{
return(buffer.NextIsDigit() ? acc + buffer.GetNumber()
: ReadCharge(acc + 1, buffer));
}
if (buffer.GetIf('-'))
{
return(buffer.NextIsDigit() ? acc - buffer.GetNumber()
: ReadCharge(acc - 1, buffer));
}
return(acc);
}
/// <summary>
/// Read the atom class of a bracket atom and progress the buffer (if read).
/// The atom class is the last attribute of the bracket atom and is
/// identified by a ':' followed by one or more digits. The atom class may be
/// padded such that ':005' and ':5' are equivalent.
/// </summary>
/// <seealso href="http://www.opensmiles.org/opensmiles.html#atomclass">Atom Class - OpenSMILES Specification</seealso >
/// <param name="buffer">a character buffer</param>
/// <returns>the atom class, or 0</returns>
public static int ReadClass(CharBuffer buffer)
{
if (buffer.GetIf(':'))
{
if (buffer.NextIsDigit())
{
return(buffer.GetNumber());
}
throw new InvalidSmilesException("invalid atom class, <digit>+ must follow ':'", buffer);
}
return(0);
}
