Added ..= operator

moonsharp-devs · Aug 10, 2023 · 267a140 · 267a140
1 parent fe4fc00
commit 267a140
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Showing 2 changed files with 27 additions and 14 deletions.
diff --git a/src/MoonSharp.Interpreter/Tree/Lexer/Lexer.cs b/src/MoonSharp.Interpreter/Tree/Lexer/Lexer.cs
@@ -175,7 +175,7 @@ private Token ReadToken()
 					{
 						char next = CursorCharNext();
 						if (next == '.')
-							return PotentiallyDoubleCharOperator('.', TokenType.Op_Concat, TokenType.VarArgs, fromLine, fromCol);
+							return PotentiallyDoubleCharOperator(TokenType.Op_Concat, '.', TokenType.VarArgs, "...", '=', TokenType.Op_Assignment, "..=", fromLine, fromCol);
 						else if (LexerUtils.CharIsDigit(next))
 							return ReadNumberToken(fromLine, fromCol, true);
 						else
@@ -545,8 +545,25 @@ private Token PotentiallyDoubleCharOperator(char expectedSecondChar, TokenType s
 			else
 				return CreateToken(singleCharToken, fromLine, fromCol, op);
 		}
+		private Token PotentiallyDoubleCharOperator(TokenType singleCharToken, char expectedSecondChar, TokenType doubleCharToken, string doubleCharText, char alternateExpectedSecondChar, TokenType alternateDoubleCharToken, string alternateDoubleCharText, int fromLine, int fromCol)
+		{
+			string op = CursorChar().ToString();
 
+			CursorCharNext();
 
+			if (CursorChar() == expectedSecondChar)
+			{
+				CursorCharNext();
+				return CreateToken(doubleCharToken, fromLine, fromCol, doubleCharText);
+			}
+			else if (CursorChar() == alternateExpectedSecondChar)
+			{
+				CursorCharNext();
+				return CreateToken(alternateDoubleCharToken, fromLine, fromCol, alternateDoubleCharText);
+			}
+			else
+				return CreateToken(singleCharToken, fromLine, fromCol, op);
+		}
 
 		private Token CreateNameToken(string name, int fromLine, int fromCol)
 		{
@@ -562,7 +579,6 @@ private Token CreateNameToken(string name, int fromLine, int fromCol)
 			}
 		}
 
-
 		private Token CreateToken(TokenType tokenType, int fromLine, int fromCol, string text = null)
 		{
 			Token t = new Token(tokenType, m_SourceId, fromLine, fromCol, m_Line, m_Col, m_PrevLineTo, m_PrevColTo)
@@ -588,9 +604,5 @@ private string ReadNameToken()
 
 			return name.ToString();
 		}
-
-
-
-
 	}
 }
diff --git a/src/MoonSharp.Interpreter/Tree/Statements/AssignmentStatement.cs b/src/MoonSharp.Interpreter/Tree/Statements/AssignmentStatement.cs
@@ -68,23 +68,24 @@ public AssignmentStatement(ScriptLoadingContext lcontext, Expression firstExpres
 				m_LValues.Add(CheckVar(lcontext, e));
 			}
 
-			char assignmentType = lcontext.Lexer.Current.Text[0];
+			string assignmentType = lcontext.Lexer.Current.Text;
 
 			CheckTokenType(lcontext, TokenType.Op_Assignment);
 
 			m_RValues = Expression.ExprList(lcontext);
 
 			// Replace e.g. "a += b" with "a = a + b"
-			if (assignmentType != '=')
+			if (assignmentType != "=")
 			{
 				TokenType ArithmeticOperation = assignmentType switch
 				{
-					'+' => TokenType.Op_Add,
-					'-' => TokenType.Op_MinusOrSub,
-					'*' => TokenType.Op_Mul,
-					'/' => TokenType.Op_Div,
-					'%' => TokenType.Op_Mod,
-					'^' => TokenType.Op_Pwr,
+					"+=" => TokenType.Op_Add,
+					"-=" => TokenType.Op_MinusOrSub,
+					"*=" => TokenType.Op_Mul,
+					"/=" => TokenType.Op_Div,
+					"%=" => TokenType.Op_Mod,
+					"^=" => TokenType.Op_Pwr,
+					"..=" => TokenType.Op_Concat,
 					_ => throw new InternalErrorException($"Assignment operator not recognised: {assignmentType}"),
 				};