// C# Eval Expression

// Doc: https://eval-expression.net/options

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// @nuget: Z.Expressions.Eval

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/*

## DefaultNumberType

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The DefaultNumberType option lets you get or get what type a number without a data type suffixes should be. For example, if you set the value to `DefaultNumberType.Double`, the expression `1+2` will consider the `1` and `2` numbers as a double instead of an `int` and will return a `double`. By default, the DefaultNumberType value is `DefaultNumberType.None`, which will act like the default C# behavior with numbers.

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In this example, we will prove that `1/2=0` by directly using a C# statement than using an expression within our library. Then, we will set the `DefaultNumberType.Double` to check the difference in the result.

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See more: https://eval-expression.net/options

*/

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using System;

using System.Collections.Generic;

using System.Reflection;

using Z.Expressions;

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public class Program

{

    public static void Main()

    {

        // Global Context: EvalManager.DefaultContext.DefaultNumberType = DefaultNumberType.Double;

        var context = new EvalContext();

        // Let proof that 1 divided by 2 equal 0 in C#

        var r1 = 1/2; // return 0

        Console.WriteLine("1 - r1 result: " + r1);

        // Let check if C# eval have the same behavior

        var r2 = context.Execute<double>("1/2"); // return 0

        Console.WriteLine("2 - r2 result: " + r2);

        // Let try again with the DefaultNumberType

        context.DefaultNumberType = DefaultNumberType.Double;

        var r3 = context.Execute<double>("1/2"); // return 0.5

        Console.WriteLine("3 - r3 result: " + r3);

    }

}

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