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Texts
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The interface **UniversalExpressionParser.IExpressionLanguageProvider** has a property **IReadOnlyList<char> ConstantTextStartEndMarkerCharacters { get; }** that are used by **Universal Expression Parser** to parse expression items that start or end with some character in **ConstantTextStartEndMarkerCharacters** to parse the expression item to **UniversalExpressionParser.ExpressionItems.IConstantTextExpressionItem**.

- The default implementation **UniversalExpressionParser.ExpressionLanguageProviderBase** of **UniversalExpressionParser.IExpressionLanguageProvider** has the following characters in property **UniversalExpressionParser.IExpressionLanguageProvider.ConstantTextStartEndMarkerCharacters** and the examples below will use these text marker characters.

- If an expression starts with some character listed in property **UniversalExpressionParser.IExpressionLanguageProvider.ConstantTextStartEndMarkerCharacters**, then the text expression should end with the same character. In other words, if text starts with character **'** it should end with **'**. Similarly, if text starts with character **"** it should end with **"**.

- The text in expression parsed to **UniversalExpressionParser.ExpressionItems.IConstantTextExpressionItem** can contain any of the text marker characters in **UniversalExpressionParser.IExpressionLanguageProvider.ConstantTextStartEndMarkerCharacters**. if the text contains a text marker character that marks the start of the text expression, it should be typed twice as displayed in examples below:

- Texts can span multiple lines (see the example below).

.. sourcecode::
     :linenos:
     
     // Example of texts using text markers ',", and ` in IExpressionLanguageProvider.ConstantTextStartEndMarkerCharacters property.
     // The text marker that starts the specific text expression can be used in text as well when it is 
     // typed twice (e.g., '', "", ``, etc).

     // Example of using all text markers together in operators
     x = "We can use this text expression marker "" if we type it twice. However, other text marker chars do not need to be typed twice such as ' and `."  
         +'We can use this text expression marker '' if we type it twice. However, other text marker chars do not need to be typed twice such as " and `.'
         +`We can use this text expression marker `` if we type it twice. However, other text marker chars do not need to be typed twice such as " and '.`;

     println("This is a text that spans
      multiple 
      lines.   
     " + x + ' Some other text.');

.. raw:: html

    <a href="https://github.com/artakhak/UniversalExpressionParser/blob/main/UniversalExpressionParser.Tests/Demos/DemoExpressions/Texts/Texts.parsed"><p class="codeSnippetRefText">Click here to see the visualized instance of UniversalExpressionParser.IParseExpressionResult</p></a>