// C# Eval Expression

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

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// @nuget: Z.Expressions.Eval

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/*

### The code

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You can provide the code to execute in 3 different ways:

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1. **Instance method:** `context.Execute(code)`

2. **Static method:** `Eval.Execute(code)`

3. **Extension method:** `"code".Execute`

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1 - In the case of the **instance method** (`context.Execute(code)`). First, you create a new instance of the [EvalContext](https://eval-expression.net/eval-context), and then you can use the `Execute` method from the context created:

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2 - In the case of the **static method** (`Eval.Execute(code)`), you can directly call the static `Eval.Execute` method, which uses  a global context under the hood. 

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3 - In the case of the **extension method** (`"code".Execute`), you can directly call the `Execute` method that extends the string type, which uses a global context under the hood. 

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One of the major differences is whether you want to create a new instance of the [EvalContext](https://eval-expression.net/eval-context) or use the global context (an instance stored in a static variable).

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We explain the answer more detail in the [EvalContext](https://eval-expression.net/eval-context) documentation, but in short:

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- If you need to customize the context for this specific evaluation, **you should** use an instance context

- If you don't need to customize the context for this specific evaluation, **you can** use the global context

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

*/

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using System;

using System.Collections.Generic;

using Z.Expressions;

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public class Program

{

    public static void Main()

    {

        // 1. **Instance method:** `context.Execute(code)`

        {

            // CREATE a new instance of EvalContext

            var context = new EvalContext();

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            // USE the `Execute` method from the context created

            var list1 = context.Execute<List<int>>("new List<int>() { 1, 2, 3 };");

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            FiddleHelper.WriteTable(list1);

        }

        // 2. **Static method:** `Eval.Execute(code)`

        {                   

            // CALL the static `Eval.Execute` method

            var list2 = Eval.Execute<List<int>>("new List<int>() { 1, 2, 3 };");

            FiddleHelper.WriteTable(list2);

        }

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        // 3. **Extension method:** `"code".Execute`

        {

            // CALL the `Execute` method that extends the string type

            var list3 = "new List<int>() { 1, 2, 3 };".Execute<List<int>>();

            FiddleHelper.WriteTable(list3);

        }

    }

}

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​