meta-language-runtime-entities-static-variables.html

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      <h1>Runtime Entities</h1>

      <div>
        <h2>Static Variables</h2>

        <p class="flow-text">
          Static variables are variables that are set by the system in a certain context and typically contain values of certain environment
          parameters in this context. Static variables, like arguments, can be used only for reading, you can not set or change them. Also,
          static variables can not be used in data substitution, in contrast to variables and arguments.
        </p>
        <p class="flow-text">
          Static variables created in a specific context are available in all valid contexts,
          and also are context-dependent.
        </p>
        <p class="flow-text">
          The following static variables are currently available:
        </p>

        <table class="responsive-table highlight">
          <thead>
          <tr>
            <th data-field="variable">Variable</th>
            <th data-field="description">Description</th>
            <th data-field="context">Context</th>
          </tr>
          </thead>

          <tbody>
          <tr>
            <td class="centered">lastUrl</td>
            <td>URL of last loaded page</td>
            <td class="centered">All</td>
          </tr>
          <tr>
            <td>url</td>
            <td>URL of current page</td>
            <td>Page, Block, Form</td>
          </tr>
          <tr>
            <td>responseCode</td>
            <td>Current HTTP request server response code</td>
            <td>Page, Block, Form</td>
          </tr>
          <tr>
            <td>filename</td>
            <td>Last saved file or image filename</td>
            <td>All</td>
          </tr>
          <tr>
            <td>object_saved</td>
            <td>If object has been saved to the DB, this variable gets value "yes". If object has been skipped (when object is saved in update mode), value will be "no".</td>
            <td>All</td>
          </tr>
          <tr>
            <td>pool_ignored</td>
            <td>Contains number of duplicate URLs that were ignored by the <span class="hlt2">link_add</span> command.</td>
            <td>All</td>
          </tr>
          </tbody>
        </table>

        <p class="flow-text">
          Despite the fact that static variables are available in practically all contexts, you can use them only in a block context,
          because the register exists only in a block context and the only command for static variables works with the register.
        </p>

        <p class="flow-text">
            Below is an example of using a static variable <span class="hlt2">url</span>:
        </p>

        <pre class="language-yaml">
          <code class="language-yaml">---
config:
    agent: Chrome
do:
- walk:
    to: http://www.somesite.com
    do:
    - find:
        path: body
        do:
        - static_get: url
        - variable_set: page_url # now we have value http://www.somesite.com in the variable with name `page_url`
          </code></pre>

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