ExpressionSample - reimplement stmt parser in terms of expr

brian-dot-net · Apr 15, 2018 · 07b7062 · 07b7062
1 parent e279c89
commit 07b7062
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Showing 5 changed files with 20 additions and 110 deletions.
diff --git a/projects/ExpressionSample/GWParse.Test/Statements/Dim.cs b/projects/ExpressionSample/GWParse.Test/Statements/Dim.cs
@@ -11,7 +11,7 @@ public sealed class Dim
         [InlineData("DIM R(1)", "Dim(NumA(R, NumL(1)))")]
         [InlineData("DIM R(1,2)", "Dim(NumA(R, NumL(1), NumL(2)))")]
         [Theory]
-        public void Valid(string input, string output)
+        public void OneItem(string input, string output)
         {
             Test.Good(input, output);
         }

diff --git a/projects/ExpressionSample/GWParse/Expressions/Expr.cs b/projects/ExpressionSample/GWParse/Expressions/Expr.cs
@@ -11,7 +11,11 @@ namespace GWParse.Expressions
 
     internal static class Expr
     {
-        private static readonly Parser<BasicExpression> Any = Parse.Ref(() => Root);
+        public static readonly Parser<BasicExpression> Any = Parse.Ref(() => Root);
+
+        public static readonly Parser<BasicExpression> AnyArray = Var.ArrayAny;
+
+        public static readonly Parser<BasicExpression> AnyVar = Var.Any;
 
         private static readonly Parser<BasicExpression> Paren =
             from lp in Ch.LeftParen
@@ -144,6 +148,10 @@ private static class Var
             public static readonly Parser<BasicExpression> NumAny = NumArray.Or(NumScalar);
 
             public static readonly Parser<BasicExpression> StrAny = StrArray.Or(StrScalar);
+
+            public static readonly Parser<BasicExpression> ArrayAny = StrArray.Or(NumArray);
+
+            public static readonly Parser<BasicExpression> Any = StrAny.Or(NumAny);
         }
 
         private static class Str

diff --git a/projects/ExpressionSample/GWParse/Statements/AssignmentStatement.cs b/projects/ExpressionSample/GWParse/Statements/AssignmentStatement.cs
@@ -4,51 +4,19 @@
 
 namespace GWParse.Statements
 {
-    using System;
     using GWParse.Expressions;
 
     internal sealed class AssignmentStatement : BasicStatement
     {
-        private static readonly IExpressionVisitor Visitor = new LValueVisitor();
-
         private readonly BasicExpression left;
         private readonly BasicExpression right;
 
         public AssignmentStatement(BasicExpression left, BasicExpression right)
         {
-            this.left = EnsureLValue(left);
+            this.left = left;
             this.right = right;
         }
 
         public override string ToString() => "Assign(" + this.left + ", " + this.right + ")";
-
-        private static BasicExpression EnsureLValue(BasicExpression left)
-        {
-            left.Accept(Visitor);
-            return left;
-        }
-
-        private sealed class LValueVisitor : IExpressionVisitor
-        {
-            public void Array(BasicType type, string name, BasicExpression[] subs)
-            {
-                // Allowed
-            }
-
-            public void Literal(BasicType type, object o)
-            {
-                throw new NotSupportedException("Not an L-value.");
-            }
-
-            public void Operator(string name, BasicExpression[] operands)
-            {
-                throw new NotSupportedException("Not an L-value.");
-            }
-
-            public void Variable(BasicType type, string name)
-            {
-                // Allowed
-            }
-        }
     }
 }
diff --git a/projects/ExpressionSample/GWParse/Statements/DimensionStatement.cs b/projects/ExpressionSample/GWParse/Statements/DimensionStatement.cs
@@ -4,49 +4,17 @@
 
 namespace GWParse.Statements
 {
-    using System;
     using GWParse.Expressions;
 
     internal sealed class DimensionStatement : BasicStatement
     {
-        private static readonly IExpressionVisitor Visitor = new ArrayVisitor();
-
         private readonly BasicExpression a;
 
         public DimensionStatement(BasicExpression a)
         {
-            this.a = EnsureArray(a);
+            this.a = a;
         }
 
         public override string ToString() => "Dim(" + this.a + ")";
-
-        private static BasicExpression EnsureArray(BasicExpression a)
-        {
-            a.Accept(Visitor);
-            return a;
-        }
-
-        private sealed class ArrayVisitor : IExpressionVisitor
-        {
-            public void Array(BasicType type, string name, BasicExpression[] subs)
-            {
-                // Allowed
-            }
-
-            public void Literal(BasicType type, object o)
-            {
-                throw new NotSupportedException("Not an array.");
-            }
-
-            public void Operator(string name, BasicExpression[] operands)
-            {
-                throw new NotSupportedException("Not an array.");
-            }
-
-            public void Variable(BasicType type, string name)
-            {
-                throw new NotSupportedException("Not an array.");
-            }
-        }
     }
 }
diff --git a/projects/ExpressionSample/GWParse/Statements/Stmt.cs b/projects/ExpressionSample/GWParse/Statements/Stmt.cs
@@ -5,6 +5,8 @@
 namespace GWParse.Statements
 {
     using System;
+    using System.Collections.Generic;
+    using System.Linq;
     using GWParse.Expressions;
     using Sprache;
 
@@ -27,14 +29,14 @@ internal static class Stmt
 
         private static readonly Parser<BasicStatement> Dim =
             from k in Parse.IgnoreCase("DIM").Token()
-            from s in Parse.AnyChar.AtLeastOnce().Text()
-            select DimA(s);
+            from a in Expr.AnyArray
+            select new DimensionStatement(a);
 
         private static readonly Parser<BasicStatement> Assign =
-            from left in Parse.CharExcept('=').AtLeastOnce().Text()
-            from o in Parse.Char('=')
-            from right in Parse.AnyChar.AtLeastOnce().Text()
-            select Asgn(left, right);
+            from left in Expr.AnyVar
+            from o in Parse.Char('=').Token()
+            from right in Expr.Any
+            select new AssignmentStatement(left, right);
 
         private static readonly Parser<BasicStatement> Any =
             Rem.Or(Cls).Or(Dim).Or(Assign);
@@ -50,41 +52,5 @@ public static BasicStatement FromString(string input)
                 throw new FormatException("Bad statement '" + input + "'.", e);
             }
         }
-
-        private static BasicStatement Asgn(string left, string right)
-        {
-            try
-            {
-                return new AssignmentStatement(Expr(left), Expr(right));
-            }
-            catch (NotSupportedException e)
-            {
-                throw new ParseException(e.Message);
-            }
-        }
-
-        private static BasicStatement DimA(string a)
-        {
-            try
-            {
-                return new DimensionStatement(Expr(a));
-            }
-            catch (NotSupportedException e)
-            {
-                throw new ParseException(e.Message);
-            }
-        }
-
-        private static BasicExpression Expr(string s)
-        {
-            try
-            {
-                return BasicExpression.FromString(s);
-            }
-            catch (FormatException e)
-            {
-                throw new ParseException(e.Message);
-            }
-        }
     }
 }