# C1.ExpressionEditor.Engine.IExpressionLexer

## Content

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  <h1 id="C1_ExpressionEditor_Engine_IExpressionLexer" data-uid="C1.ExpressionEditor.Engine.IExpressionLexer" class="text-break">IExpressionLexer Interface
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  <div class="markdown level0 summary"><p>Defines the lexical dictionary of expression engine.</p>
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  <div class="markdown level0 conceptual"></div>
  <h6><strong>Namespace</strong>: <a class="xref" href="C1.ExpressionEditor.Engine.html">C1.ExpressionEditor.Engine</a></h6>
  <h6><strong>Assembly</strong>: C1.Win.ExpressionEditor.10.dll</h6>
  <h5 id="C1_ExpressionEditor_Engine_IExpressionLexer_syntax">Syntax</h5>
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    <pre><code class="lang-csharp hljs">public interface IExpressionLexer</code></pre>
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  <div class="codewrapper">
    <pre><code class="lang-vbnet hljs">Public Interface IExpressionLexer</code></pre>
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  <h3 id="methods">Methods
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  <table class="table table-bordered table-condensed">
    <thead>
      <tr>
        <th>Name</th>
        <th>Description</th>
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        <td id="C1_ExpressionEditor_Engine_IExpressionLexer_AddFunction_System_Collections_Generic_List_C1_ExpressionEditor_Engine_ExpressionItem__System_Func_System_Collections_Generic_List_System_Object__System_Object__System_Int32_System_Int32_" data-uid="C1.ExpressionEditor.Engine.IExpressionLexer.AddFunction(System.Collections.Generic.List{C1.ExpressionEditor.Engine.ExpressionItem},System.Func{System.Collections.Generic.List{System.Object},System.Object},System.Int32,System.Int32)">
          <a class="xref" href="C1.ExpressionEditor.Engine.IExpressionLexer.AddFunction.html#C1_ExpressionEditor_Engine_IExpressionLexer_AddFunction_System_Collections_Generic_List_C1_ExpressionEditor_Engine_ExpressionItem__System_Func_System_Collections_Generic_List_System_Object__System_Object__System_Int32_System_Int32_">AddFunction(List&lt;ExpressionItem&gt;, Func&lt;List&lt;object&gt;, object&gt;, int, int)</a>
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        <td class="markdown level1 summary"><p>Added a custom function to engine of C1ExpressionEditor.</p>
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        <td id="C1_ExpressionEditor_Engine_IExpressionLexer_GetExpressionItems" data-uid="C1.ExpressionEditor.Engine.IExpressionLexer.GetExpressionItems">
          <a class="xref" href="C1.ExpressionEditor.Engine.IExpressionLexer.GetExpressionItems.html#C1_ExpressionEditor_Engine_IExpressionLexer_GetExpressionItems">GetExpressionItems()</a>
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        <td class="markdown level1 summary"><p>Gets list of <a class="xref" href="C1.ExpressionEditor.Engine.ExpressionItem.html">ExpressionItem</a> of the current context.</p>
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  </table>

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