#304 - Parse binary assign as expression

sys27 · Oct 1, 2020 · 47d4787 · 47d4787
1 parent 2b0caa6
commit 47d4787
Show file tree

Hide file tree

Showing 9 changed files with 217 additions and 68 deletions.
diff --git a/xFunc Grammar.txt b/xFunc Grammar.txt
@@ -10,9 +10,6 @@ statement = unaryAssign
           / while
           / exp
 
-unaryAssign = variable ('++' / '--')
-binaryAssign = variable ('+=' / '-=' / '*=' / '/=' / '<<=' / '>>=') exp
-
 assignmentKey = functionDeclaration / variable
 assign = assignmentKey ':=' exp
 def = ('def' / 'define') '(' assignmentKey ',' exp ')'
@@ -22,8 +19,10 @@ if = 'if' '(' conditional ',' exp (',' exp)* ')'
 for = 'for' '(' statement ',' exp ',' conditional ',' statement ')'
 while = 'while' '(' exp ',' conditional ')'
 
-exp = ternary 
+exp = binaryAssign
+    / ternary 
 
+binaryAssign = variable ('+=' / '-=' / '*=' / '/=' / '<<=' / '>>=') exp
 ternary = conditional ('?' exp ':' exp)*
 
 conditional = bitwise (('&&' / '||') bitwise)*
@@ -36,7 +35,12 @@ mulImplicit = mulImplicitLeftUnary / leftUnary
 mulImplicitLeftUnary = '-'* number rightUnary
 leftUnary = ('~' / '-')* exponentiation
 exponentiation = rightUnary ('^' exponentiation)*
-rightUnary = (number '!') / operand
+rightUnary = incDec
+           / factorial
+           / operand
+
+incDec = variable ('++' / '--')
+factorial = (number '!')
 
 operand = complexnumber /
           number /

diff --git a/xFunc.Maths/Parser.cs b/xFunc.Maths/Parser.cs
@@ -103,40 +103,6 @@ public IExpression Parse(string function)
                ParseWhile(ref tokenReader) ??
                ParseExpression(ref tokenReader);
 
-        private IExpression? ParseBinaryAssign(ref TokenReader tokenReader)
-        {
-            var scope = tokenReader.CreateScope();
-
-            var left = ParseVariable(ref tokenReader);
-            if (left == null)
-            {
-                tokenReader.Rollback(scope);
-
-                return null;
-            }
-
-            var @operator = tokenReader.GetCurrent(MulAssignOperator) ||
-                            tokenReader.GetCurrent(DivAssignOperator) ||
-                            tokenReader.GetCurrent(AddAssignOperator) ||
-                            tokenReader.GetCurrent(SubAssignOperator) ||
-                            tokenReader.GetCurrent(LeftShiftAssignOperator) ||
-                            tokenReader.GetCurrent(RightShiftAssignOperator);
-
-            if (@operator.IsNotEmpty())
-            {
-                var right = ParseExpression(ref tokenReader) ??
-                            MissingSecondOperand(@operator.Kind);
-
-                tokenReader.Commit();
-
-                return CreateBinaryAssign(@operator, left, right);
-            }
-
-            tokenReader.Rollback(scope);
-
-            return null;
-        }
-
         private IExpression? AssignmentKey(ref TokenReader tokenReader)
             => ParseFunctionDeclaration(ref tokenReader) ??
                ParseVariable(ref tokenReader);
@@ -345,7 +311,42 @@ public IExpression Parse(string function)
         }
 
         private IExpression? ParseExpression(ref TokenReader tokenReader)
-            => Ternary(ref tokenReader);
+            => ParseBinaryAssign(ref tokenReader) ??
+               Ternary(ref tokenReader);
+
+        private IExpression? ParseBinaryAssign(ref TokenReader tokenReader)
+        {
+            var scope = tokenReader.CreateScope();
+
+            var variable = ParseVariable(ref tokenReader);
+            if (variable == null)
+            {
+                tokenReader.Rollback(scope);
+
+                return null;
+            }
+
+            var @operator = tokenReader.GetCurrent(MulAssignOperator) ||
+                            tokenReader.GetCurrent(DivAssignOperator) ||
+                            tokenReader.GetCurrent(AddAssignOperator) ||
+                            tokenReader.GetCurrent(SubAssignOperator) ||
+                            tokenReader.GetCurrent(LeftShiftAssignOperator) ||
+                            tokenReader.GetCurrent(RightShiftAssignOperator);
+
+            if (@operator.IsNotEmpty())
+            {
+                var exp = ParseExpression(ref tokenReader) ??
+                          MissingSecondOperand(@operator.Kind);
+
+                tokenReader.Commit();
+
+                return CreateBinaryAssign(@operator, variable, exp);
+            }
+
+            tokenReader.Rollback(scope);
+
+            return null;
+        }
 
         private IExpression? Ternary(ref TokenReader tokenReader)
         {

diff --git a/xFunc.Tests/Expressions/Programming/AddAssignTest.cs b/xFunc.Tests/Expressions/Programming/AddAssignTest.cs
@@ -36,6 +36,17 @@ public void AddAssignCalc()
             Assert.Equal(expected, parameters["x"]);
         }
 
+        [Fact]
+        public void AddAssignAsExpressionTest()
+        {
+            var parameters = new ParameterCollection { new Parameter("x", 10) };
+            var add = new Add(Number.One, new AddAssign(Variable.X, Number.Two));
+            var result = add.Execute(parameters);
+
+            Assert.Equal(13.0, result);
+            Assert.Equal(12.0, parameters["x"]);
+        }
+
         [Fact]
         public void AddNullParameters()
         {

diff --git a/xFunc.Tests/Expressions/Programming/DivAssignTest.cs b/xFunc.Tests/Expressions/Programming/DivAssignTest.cs
@@ -36,6 +36,17 @@ public void DivAssignCalc()
             Assert.Equal(expected, parameters["x"]);
         }
 
+        [Fact]
+        public void DivAssignAsExpressionTest()
+        {
+            var parameters = new ParameterCollection { new Parameter("x", 10) };
+            var add = new Div(new AddAssign(Variable.X, Number.Two), Number.Two);
+            var result = add.Execute(parameters);
+
+            Assert.Equal(6.0, result);
+            Assert.Equal(12.0, parameters["x"]);
+        }
+
         [Fact]
         public void DivNullParameters()
         {

diff --git a/xFunc.Tests/Expressions/Programming/LeftShiftAssignTest.cs b/xFunc.Tests/Expressions/Programming/LeftShiftAssignTest.cs
@@ -38,6 +38,20 @@ public void ExecuteTest()
             Assert.Equal(expected, actual);
         }
 
+        [Fact]
+        public void ExecuteAsExpressionTest()
+        {
+            var exp = new Add(Number.One, new LeftShiftAssign(Variable.X, new Number(10)));
+            var parameters = new ParameterCollection
+            {
+                new Parameter("x", 1.0)
+            };
+            var actual = exp.Execute(parameters);
+
+            Assert.Equal(1025.0, actual);
+            Assert.Equal(1024.0, parameters["x"]);
+        }
+
         [Fact]
         public void ExecuteNullParamsTest()
         {

diff --git a/xFunc.Tests/Expressions/Programming/MulAssignTest.cs b/xFunc.Tests/Expressions/Programming/MulAssignTest.cs
@@ -36,6 +36,17 @@ public void MulAssignCalc()
             Assert.Equal(expected, parameters["x"]);
         }
 
+        [Fact]
+        public void MulAssignAsExpressionTest()
+        {
+            var parameters = new ParameterCollection { new Parameter("x", 10) };
+            var add = new Mul(Number.Two, new AddAssign(Variable.X, Number.Two));
+            var result = add.Execute(parameters);
+
+            Assert.Equal(24.0, result);
+            Assert.Equal(12.0, parameters["x"]);
+        }
+
         [Fact]
         public void MulNullParameters()
         {

diff --git a/xFunc.Tests/Expressions/Programming/RightShiftAssignTest.cs b/xFunc.Tests/Expressions/Programming/RightShiftAssignTest.cs
@@ -38,6 +38,20 @@ public void ExecuteTest()
             Assert.Equal(expected, actual);
         }
 
+        [Fact]
+        public void ExecuteAsExpressionTest()
+        {
+            var exp = new Add(Number.One, new RightShiftAssign(Variable.X, new Number(9)));
+            var parameters = new ParameterCollection
+            {
+                new Parameter("x", 512.0)
+            };
+            var actual = exp.Execute(parameters);
+
+            Assert.Equal(2.0, actual);
+            Assert.Equal(1.0, parameters["x"]);
+        }
+
         [Fact]
         public void ExecuteNullParamsTest()
         {

diff --git a/xFunc.Tests/Expressions/Programming/SubAssignTest.cs b/xFunc.Tests/Expressions/Programming/SubAssignTest.cs
@@ -36,6 +36,17 @@ public void SubAssignCalc()
             Assert.Equal(expected, parameters["x"]);
         }
 
+        [Fact]
+        public void SubAssignAsExpressionTest()
+        {
+            var parameters = new ParameterCollection { new Parameter("x", 10) };
+            var add = new Sub(Number.One, new AddAssign(Variable.X, Number.Two));
+            var result = add.Execute(parameters);
+
+            Assert.Equal(-11.0, result);
+            Assert.Equal(12.0, parameters["x"]);
+        }
+
         [Fact]
         public void SubNullParameters()
         {