Simplify handlers

src/Ramstack.ExpressionParser/Binder.cs

@@ -18,7 +18,7 @@ public abstract class Binder
     /// </summary>
     /// <param name="name">The <see cref="Identifier"/> representing the name of the requested type.</param>
     /// <returns>
-    /// The <see cref="Type"/> instance corresponding to the specified <paramref name="name"/> 
+    /// The <see cref="Type"/> instance corresponding to the specified <paramref name="name"/>
     /// if resolved successfully; otherwise, <see langword="null"/>.
     /// </returns>
     public abstract Type? BindToType(Identifier name);

src/Ramstack.ExpressionParser/DefaultBinder.cs

@@ -128,7 +128,9 @@ public void RegisterType(Type type, bool importAsStatic = false)
     /// <inheritdoc />
     public override MemberInfo? BindToMember(Type? type, Identifier memberName, bool isStatic)
     {
-        var bindingFlags = BindingFlags.Public | (isStatic ? BindingFlags.Static : BindingFlags.Instance);
+        var bindingFlags = isStatic
+            ? BindingFlags.Public | BindingFlags.Static
+            : BindingFlags.Public | BindingFlags.Instance;
 
         var q = type?.GetMembers(bindingFlags)
             ?? PredefinedType
@@ -158,8 +160,9 @@ private static IEnumerable<MethodBase> GetMethods(Type type, string methodName,
             ? BindingFlags.Public | BindingFlags.InvokeMethod | BindingFlags.Static
             : BindingFlags.Public | BindingFlags.InvokeMethod | BindingFlags.Instance;
 
-        return type.GetMethods(bindingFlags)
-            .Where(m => StringComparer.OrdinalIgnoreCase.Equals(m.Name, methodName))
+        return type
+            .GetMethods(bindingFlags)
+            .Where(m => string.Equals(m.Name, methodName, StringComparison.OrdinalIgnoreCase))
             .Distinct();
     }
 }

src/Ramstack.ExpressionParser/ExpressionBuilder.Helpers.cs

@@ -71,9 +71,14 @@ private static List<Expression> CreateInjectingArguments(MethodInfo method, IRea
                 var paramArrayType = parameter.ParameterType.GetElementType()!;
 
                 for (; i < args.Count; i++)
-                    paramArray.Add(Convert(args[i], paramArrayType));
+                    paramArray.Add(
+                        Convert(args[i], paramArrayType));
+
+                list.Add(
+                    Expression.NewArrayInit(
+                        paramArrayType,
+                        paramArray));
 
-                list.Add(Expression.NewArrayInit(paramArrayType, paramArray));
                 break;
             }
 
@@ -112,10 +117,8 @@ private static Expression ApplyBinaryExpression(Identifier op, Func<Expression,
         if (enumUnderlyingType is not null)
         {
             if (lhs.Type != rhs.Type)
-            {
                 if (lhs.Type.IsEnum ? enumUnderlyingType != rhs.Type : enumUnderlyingType != lhs.Type)
                     Error.NonApplicableBinaryOperator(op, lhs.Type, rhs.Type);
-            }
 
             if (lhs.Type.IsEnum)
                 lhs = Expression.Convert(lhs, enumUnderlyingType);
@@ -128,35 +131,35 @@ private static Expression ApplyBinaryExpression(Identifier op, Func<Expression,
         {
             if (!TypeUtils.IsInteger(lhs.Type) && TypeUtils.IsInteger(rhs.Type))
                 Error.NonApplicableBinaryOperator(op, lhs.Type, rhs.Type);
-        
+
             if (rhs.Type == typeof(sbyte)
                 || rhs.Type == typeof(byte)
                 || rhs.Type == typeof(short)
                 || rhs.Type == typeof(ushort))
                 rhs = Expression.Convert(rhs, typeof(int));
-        
+
             if (rhs.Type != typeof(int))
                 Error.NonApplicableBinaryOperator(op, lhs.Type, rhs.Type);
-        
+
             if (lhs.Type == typeof(sbyte)
                 || lhs.Type == typeof(byte)
                 || lhs.Type == typeof(short)
                 || lhs.Type == typeof(ushort))
                 lhs = Expression.Convert(lhs, typeof(int));
-        
+
             if (op.Name == ">>>")
             {
                 if (lhs.Type == typeof(int))
                     return Expression.Convert(
                         apply(Expression.Convert(lhs, typeof(uint)), rhs),
                         typeof(int));
-        
+
                 if (lhs.Type == typeof(long))
                     return Expression.Convert(
                         apply(Expression.Convert(lhs, typeof(ulong)), rhs),
                         typeof(long));
             }
-        
+
             return apply(lhs, rhs);
         }
 
@@ -183,12 +186,28 @@ private static Expression ApplyBinaryExpression(Identifier op, Func<Expression,
         return result;
     }
 
-    //
-    // 12.4.7 Numeric promotions
-    // https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/language-specification/expressions#1247-numeric-promotions
-    //
     private static void ApplyBinaryNumericPromotions(Identifier op, ref Expression lhs, ref Expression rhs)
     {
+        //
+        // 12.4.7.3 Binary numeric promotions
+        // https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/language-specification/expressions#12473-binary-numeric-promotions
+        //
+        // Binary numeric promotion implicitly converts both operands to a common type which,
+        // in case of the non-relational operators, also becomes the result type of the operation.
+        // Binary numeric promotion consists of applying the following rules, in the order they appear here:
+        //
+        // * If either operand is of type decimal, the other operand is converted to type decimal,
+        //   or a binding-time error occurs if the other operand is of type float or double.
+        // * Otherwise, if either operand is of type double, the other operand is converted to type double.
+        // * Otherwise, if either operand is of type float, the other operand is converted to type float.
+        // * Otherwise, if either operand is of type ulong, the other operand is converted to type ulong,
+        //   or a binding-time error occurs if the other operand is of type sbyte, short, int, or long.
+        // * Otherwise, if either operand is of type long, the other operand is converted to type long.
+        // * Otherwise, if either operand is of type uint and the other operand is of type sbyte, short, or int,
+        //   both operands are converted to type long.
+        // * Otherwise, if either operand is of type uint, the other operand is converted to type uint.
+        // * Otherwise, both operands are converted to type int.
+
         var lhsType = lhs.Type;
         var rhsType = rhs.Type;
 
@@ -218,8 +237,10 @@ private static void ApplyBinaryNumericPromotions(Identifier op, ref Expression l
 
             if (conversionType == typeof(decimal))
             {
+                //
                 // If either operand is of type decimal, the other operand is converted to type decimal,
                 // or a compile-time error occurs if the other operand is of type float or double.
+                //
                 if (lhsType == typeof(double)
                     || lhsType == typeof(float)
                     || rhsType == typeof(double)
@@ -228,8 +249,10 @@ private static void ApplyBinaryNumericPromotions(Identifier op, ref Expression l
             }
             else if (conversionType == typeof(ulong))
             {
-                // if either operand is of type ulong, the other operand is converted to type ulong,
+                //
+                // If either operand is of type ulong, the other operand is converted to type ulong,
                 // or a compile-time error occurs if the other operand is of type sbyte, short, int, or long.
+                //
                 if (lhsType == typeof(sbyte)
                     || lhsType == typeof(short)
                     || lhsType == typeof(int)
@@ -242,8 +265,10 @@ private static void ApplyBinaryNumericPromotions(Identifier op, ref Expression l
             }
             else if (conversionType == typeof(uint))
             {
-                // if either operand is of type uint and the other operand is of type sbyte, short, or int,
+                //
+                // If either operand is of type uint and the other operand is of type sbyte, short, or int,
                 // both operands are converted to type long.
+                //
                 if (lhsType == typeof(sbyte)
                     || lhsType == typeof(short)
                     || lhsType == typeof(int)
@@ -263,25 +288,25 @@ private static void ApplyBinaryNumericPromotions(Identifier op, ref Expression l
         }
     }
 
-    private static Func<Expression, Expression, Expression> CreateOperatorFactory(string @operator)
+    private static Func<Expression, Expression, Expression> ResolveBinaryOperatorFactory(string @operator)
     {
         return @operator switch
         {
             "??" => Expression.Coalesce,
-            "||" => Expression.OrElse,
             "&&" => Expression.AndAlso,
-            "|" => Expression.Or,
-            "^" => Expression.ExclusiveOr,
-            "&" => Expression.And,
+            "||" => Expression.OrElse,
             "==" => Expression.Equal,
             "!=" => Expression.NotEqual,
             "<=" => Expression.LessThanOrEqual,
-            "<" => Expression.LessThan,
             ">=" => Expression.GreaterThanOrEqual,
-            ">" => Expression.GreaterThan,
             ">>" => Expression.RightShift,
-            ">>>" => Expression.RightShift,
             "<<" => Expression.LeftShift,
+            ">>>" => Expression.RightShift,
+            "<" => Expression.LessThan,
+            ">" => Expression.GreaterThan,
+            "&" => Expression.And,
+            "|" => Expression.Or,
+            "^" => Expression.ExclusiveOr,
             "+" => Expression.Add,
             "-" => Expression.Subtract,
             "*" => Expression.Multiply,

src/Ramstack.ExpressionParser/ExpressionBuilder.cs

@@ -37,38 +37,38 @@ protected internal override Expression VisitBinary(Expr.Binary expr)
         var lhs = Visit(expr.Left);
         var rhs = Visit(expr.Right);
 
-        var factory = CreateOperatorFactory(expr.Operator.Name);
+        var lhsType = lhs.Type;
+        var rhsType = rhs.Type;
 
-        var l = lhs;
-        var r = rhs;
+        var factory = ResolveBinaryOperatorFactory(expr.Operator.Name);
 
         switch (expr.Operator.Name)
         {
             case "&&":
             case "||":
-                l = ApplyImplicitConversion(lhs, typeof(bool));
-                r = ApplyImplicitConversion(rhs, typeof(bool));
+                lhs = ApplyImplicitConversion(lhs, typeof(bool));
+                rhs = ApplyImplicitConversion(rhs, typeof(bool));
 
-                if (l is null)
-                    Error.MissingImplicitConversion(lhs.Type, typeof(bool));
+                if (lhs is null)
+                    Error.MissingImplicitConversion(lhsType, typeof(bool));
 
-                if (r is null)
-                    Error.MissingImplicitConversion(rhs.Type, typeof(bool));
+                if (rhs is null)
+                    Error.MissingImplicitConversion(rhsType, typeof(bool));
 
                 break;
 
             case "??":
-                if (lhs.Type.IsValueType && !lhs.Type.IsNullable())
-                    Error.NonApplicableBinaryOperator(expr.Operator, lhs.Type, rhs.Type);
+                if (lhsType.IsValueType && !lhsType.IsNullable())
+                    Error.NonApplicableBinaryOperator(expr.Operator, lhsType, rhsType);
 
-                r = ApplyImplicitConversion(rhs, lhs.Type);
-                if (r is null)
-                    Error.NonApplicableBinaryOperator(expr.Operator, lhs.Type, rhs.Type);
+                rhs = ApplyImplicitConversion(rhs, lhsType);
+                if (rhs is null)
+                    Error.NonApplicableBinaryOperator(expr.Operator, lhsType, rhsType);
 
                 break;
 
             case "+":
-                if (lhs.Type != typeof(string) && rhs.Type != typeof(string))
+                if (lhsType != typeof(string) && rhsType != typeof(string))
                     break;
 
                 var arguments = new List<Expression>();
@@ -137,11 +137,11 @@ void Flatten(Expression e)
 
         try
         {
-            return ApplyBinaryExpression(expr.Operator, factory, l, r);
+            return ApplyBinaryExpression(expr.Operator, factory, lhs, rhs);
         }
         catch (Exception e) when (e is not ParseErrorException)
         {
-            Error.NonApplicableBinaryOperator(expr.Operator, lhs.Type, rhs.Type);
+            Error.NonApplicableBinaryOperator(expr.Operator, lhsType, rhsType);
         }
 
         return null!;

src/Ramstack.ExpressionParser/ExpressionParser.Parser.cs

@@ -42,7 +42,8 @@ private static Parser<Expr> CreateParser()
             ).Void();
 
         var number_literal =
-            ConstantNumberParser.NumericLiteral
+            ConstantNumberParser
+                .NumericLiteral
                 .Do(Expr (v) => new Expr.Literal(v));
 
         var string_literal =
@@ -187,57 +188,57 @@ static Expr HijackMemberExpression(Expr result, Expr value)
 
         var mul_expression =
             prefix_expression.Fold(
-                OneOf("*/%").ThenIgnore(S).Map(CreateIdentifier),
+                OneOf("*/%").ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var add_expression =
             mul_expression.Fold(
-                OneOf("+-").ThenIgnore(S).Map(CreateIdentifier),
+                OneOf("+-").ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var shift_expression =
             add_expression.Fold(
-                OneOf(["<<", ">>", ">>>"]).ThenIgnore(S).Map(CreateIdentifier),
+                OneOf(["<<", ">>", ">>>"]).ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var relational_expression =
             shift_expression.Fold(
-                OneOf(["<", ">", "<=", ">="]).ThenIgnore(S).Map(CreateIdentifier),
+                OneOf(["<", ">", "<=", ">="]).ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var equality_expression =
             relational_expression.Fold(
-                OneOf("==", "!=").ThenIgnore(S).Map(CreateIdentifier),
+                OneOf("==", "!=").ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var bitwise_and_expression =
             equality_expression.Fold(
-                L('&').ThenIgnore(S).Map(CreateIdentifier),
+                L('&').ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var bitwise_xor_expression =
             bitwise_and_expression.Fold(
-                L('^').ThenIgnore(S).Map(CreateIdentifier),
+                L('^').ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var bitwise_or_expression =
             bitwise_xor_expression.Fold(
-                L('|').ThenIgnore(S).Map(CreateIdentifier),
+                L('|').ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var logical_and_expression =
             bitwise_or_expression.Fold(
-                L("&&").ThenIgnore(S).Map(CreateIdentifier),
+                L("&&").ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var logical_or_expression =
             logical_and_expression.Fold(
-                L("||").ThenIgnore(S).Map(CreateIdentifier),
+                L("||").ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var null_coalesce_expression =
             logical_or_expression.FoldR(
-                L("??").ThenIgnore(S).Map(CreateIdentifier),
+                L("??").ThenIgnore(S).Do(CreateIdentifier),
                 (lhs, rhs, op) => new Expr.Binary(op, lhs, rhs));
 
         var conditional_expression = Deferred<Expr>();
@@ -261,9 +262,9 @@ static Expr HijackMemberExpression(Expr result, Expr value)
         return S.Then(expression);
     }
 
-    private static Identifier CreateIdentifier(Match m, string v) =>
-        new(v);
+    private static Identifier CreateIdentifier(string v) =>
+        new Identifier(v);
 
-    private static Identifier CreateIdentifier(Match m, char v) =>
-        new(new string(v, 1));
+    private static Identifier CreateIdentifier(char v) =>
+        new Identifier(v.ToString());
 }

src/Ramstack.ExpressionParser/Expressions/Expr.Unary.cs

@@ -3,7 +3,7 @@ namespace Ramstack.Parsing.Expressions;
 partial class Expr
 {
     /// <summary>
-    /// Represents an unary operation expression in an expression tree, consisting of an operator and a single operand.
+    /// Represents a unary operation expression in an expression tree, consisting of an operator and a single operand.
     /// </summary>
     /// <param name="operator">The <see cref="Identifier"/> representing the unary operator, e.g., <c>"-"</c> or <c>"int"</c>.</param>
     /// <param name="unaryType">The <see cref="UnaryType"/> specifying the kind of unary operation (e.g., arithmetic or conversion).</param>