Initial commit

`Tokenizer` can _just barely_ parse a basic, well-formed move list.

Initially, I wanted to provide the movetext as a `Stream` rather than a
string, the idea being that it could be processed as it was being read
from a file without having to read the entire file into memory first. I
had difficulties with the stream being unreadable in
`Tokenizer.ParseMoves()`, so I switched to a string in order to get the
actual parsing logic down first.

Because of the `yield return` strategy, the debug console output
includes all of the expected halfmoves multiple times in various orders.
After running a test, generally the full, in-order list seems to exist
at the bottom of the output.

1 files changed, 22 insertions, 0 deletions

diff --git a/DotnetPgn/PieceParser.cs b/DotnetPgn/PieceParser.cs
new file mode 100644
index 0000000..5ea9402
--- /dev/null
+++ b/DotnetPgn/PieceParser.cs
@@ -0,0 +1,22 @@
+using System;

+using DotnetPgn.Models;

+

+namespace DotnetPgn

+{

+    public static class PieceParser

+    {

+        public static Piece ParsePiece(string sanPiece)

+        {

+            return sanPiece switch

+            {

+                "P" or "p" or "" => Piece.Pawn,

+                "N" or "n" => Piece.Knight,

+                "B" or "b" => Piece.Bishop,

+                "R" or "r" => Piece.Rook,

+                "Q" or "q" => Piece.Queen,

+                "K" or "k" => Piece.King,

+                _ => throw new ArgumentException($"'{sanPiece} is not a valid piece.'"),

+            };

+        }

+    }

+}