Version 1.2.1.3: Added support for string case conversion (tolower / …

…toupper)

MathConverter/Parser.cs

@@ -295,6 +295,7 @@ private AbstractSyntaxTree Primary()
                     var lex = (t as LexicalToken).Lex;
                     Func<object> formula0 = null;
                     Func<double, double> formula1 = null;
+                    Func<object, object> formula1_obj = null;
                     Func<object, object, object> formula2 = null;
                     Func<IEnumerable<object>, object> formulaN = null;
                     switch (lex.ToLower())
@@ -353,6 +354,14 @@ private AbstractSyntaxTree Primary()
                                 case "rad":
                                     formula1 = x => x / 180 * Math.PI;
                                     break;
+                                case "tolower":
+                                case "lcase":
+                                    formula1_obj = x => x == null ? null : $"{x}".ToLowerInvariant();
+                                    break;
+                                case "toupper":
+                                case "ucase":
+                                    formula1_obj = x => x == null ? null : $"{x}".ToUpperInvariant();
+                                    break;
                                 case "round":
                                     formula2 = (x, y) =>
                                     {
@@ -465,7 +474,7 @@ private AbstractSyntaxTree Primary()
 
                         return new FormulaNode0(lex, formula0);
                     }
-                    else if (formula1 != null)
+                    else if (formula1 != null || formula1_obj != null)
                     {
                         // Create a formula1.
                         var ex = $"{lex} is a formula that takes one argument.  You must specify the arguments like this: \"{lex}(3)\"";
@@ -487,7 +496,19 @@ private AbstractSyntaxTree Primary()
                         if (scanner.GetToken().TokenType != TokenType.RParen)
                             throw new ParsingException(scanner.Position, ex);
 
-                        return new FormulaNode1(lex, formula1, arg);
+                        if (formula1 != null)
+                        {
+                            formula1_obj = x =>
+                            {
+                                var val = MathConverter.ConvertToDouble(x);
+                                if (val.HasValue)
+                                    return formula1(val.Value);
+                                else
+                                    return null;
+                            };
+                        }
+
+                        return new FormulaNode1(lex, formula1_obj, arg);
                     }
                     else if (formula2 != null)
                     {

MathConverter/Properties/AssemblyInfo.cs

@@ -51,8 +51,8 @@
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
 // [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.2.1.2")]
-[assembly: AssemblyFileVersion("1.2.1.2")]
+[assembly: AssemblyVersion("1.2.1.3")]
+[assembly: AssemblyFileVersion("1.2.1.3")]
 
 [assembly: XmlnsPrefix("http://hexinnovation.com/math", "math")]
 [assembly: XmlnsDefinition("http://hexinnovation.com/math", "HexInnovation")]

MathConverter/SyntaxTree.cs

@@ -483,23 +483,19 @@ public override string ToString()
     /// </summary>
     class FormulaNode1 : AbstractSyntaxTree
     {
-        public FormulaNode1(string FormulaName, Func<double, double> formula, AbstractSyntaxTree input)
+        public FormulaNode1(string FormulaName, Func<object, object> formula, AbstractSyntaxTree input)
         {
             this.FormulaName = FormulaName;
             this.formula = formula;
             this.input = input;
         }
         private string FormulaName;
-        private Func<double, double> formula;
+        private Func<object, object> formula;
         private AbstractSyntaxTree input;
 
         public override object Evaluate(object[] Parameters)
         {
-            var value = MathConverter.ConvertToDouble(input.Evaluate(Parameters));
-            if (value == null)
-                return null;
-            else
-                return formula(value.Value);
+            return formula(input.Evaluate(Parameters));
         }
         public override string ToString()
         {

README.md

@@ -315,7 +315,7 @@ The Converter `format("Language {0}: {1}",x+1,y)` will essentially `return strin
 
 The real magic being done here is in the [`System.String.Format`](https://msdn.microsoft.com/en-us/library/b1csw23d(v=vs.110).aspx) method. If you unfamiliar with this method, you can see a lot of examples [here](http://msdn.microsoft.com/en-us/library/txafckwd).
 
-`format` is another example of an N-value function. The only difference is that this particular function does not return a numeric value, but rather returns a string. Other non-numeric N-value functions are: `and`, `or`, `nor`. These functions take and return boolean values. The zero-value function function `now()` returns [`System.DateTime.Now`](https://msdn.microsoft.com/en-us/library/system.datetime.now(v=vs.110).aspx)
+`format` is another example of an N-value function. The only difference is that this particular function does not return a numeric value, but rather returns a string. Other non-numeric N-value functions are: `and`, `or`, `nor`. These functions take and return boolean values. The zero-value function function `now()` returns [`System.DateTime.Now`](https://msdn.microsoft.com/en-us/library/system.datetime.now(v=vs.110).aspx). There are also one-value functions useful for case-conversion: `tolower` / `lcase`, and `toupper` / `ucase`. When passed `null`, these functions will return `null`. When passed an object, they will call `ToString()` on the object and then convert to lower/upper case.
 
 Let's look again at the `ConverterParameter` in the previous example: `ConverterParameter="format("Language {0}: {1}",x+1,y)"`. Because this is xaml, the `"` characters are converted to `"` characters. Thus, at runtime, the `ConverterParameter` is `format("Language {0}: {1}",x+1,y)`. When `MathConverter` parses the `ConverterParameter`, it sees that "Language {0}: {1}" is a string. In order to include special characters in the string, you can simply backslash-escape them, just like you're used to. So `\r`, `\n`, `\"`, and `\t` (among others) are valid special characters that can be added to strings. At the moment, arbitrary unicode characters (such as `\u0000`) are not supported, but these can be added if there is sufficient demand.
 

UnitTests/UnitTests.cs

@@ -612,6 +612,13 @@ public void TestFunctions()
             Assert.AreEqual(true, Converter.Convert(new object[] { new object[] { "hello", "world" } }, typeof(object), "contains(x, `hello`)", CultureInfo.GetCultureInfo("de")));
             Assert.AreEqual(false, Converter.Convert(new object[] { new object[] { "hello", "world" } }, typeof(object), "contains(x, `Hello`)", CultureInfo.GetCultureInfo("de")));
 
+            Assert.AreEqual(true, Converter.Convert(new object[] { "ψñíçθдë têsт", "ΨÑÍÇΘДË TÊSТ" }, typeof(object), "toupper(x) == y", CultureInfo.GetCultureInfo("de")));
+            Assert.AreEqual(true, Converter.Convert(new object[] { "ψñíçθдë têsт", "ΨÑÍÇΘДË TÊSТ" }, typeof(object), "tolower(y) == x", CultureInfo.GetCultureInfo("de")));
+            Assert.AreEqual(true, Converter.Convert(new object[] { "ψñíçθдë têsт", "ΨÑÍÇΘДË TÊSТ" }, typeof(object), "toupper(y) == y", CultureInfo.GetCultureInfo("de")));
+            Assert.AreEqual(true, Converter.Convert(new object[] { "ψñíçθдë têsт", "ΨÑÍÇΘДË TÊSТ" }, typeof(object), "tolower(x) == x", CultureInfo.GetCultureInfo("de")));
+            Assert.AreEqual(true, Converter.Convert(new object[] { "ψñíçθдë têsт", "ΨÑÍÇΘДË TÊSТ" }, typeof(object), "toupper(y) != tolower(y)", CultureInfo.GetCultureInfo("de")));
+            Assert.AreEqual(true, Converter.Convert(new object[] { "ψñíçθдë têsт", "ΨÑÍÇΘДË TÊSТ" }, typeof(object), "toupper(x) != tolower(x)", CultureInfo.GetCultureInfo("de")));
+
             foreach (var x in new bool[] { true, false })
             {
                 Assert.AreEqual(x, Converter.Convert(new object[] { x }, typeof(object), "and(AND(true,true,true,true,true),x,true)", CultureInfo.GetCultureInfo("de")));