Add children to heading.

src/context/document_element.rs

@@ -1,5 +1,11 @@
+use std::path::Path;
+
 use serde::Serialize;
 
+use crate::config::Config;
+use crate::error::CustomError;
+use crate::intermediate::IDocumentElement;
+
 use super::RenderHeading;
 use super::RenderSection;
 
@@ -9,3 +15,21 @@ pub(crate) enum RenderDocumentElement {
     Heading(RenderHeading),
     Section(RenderSection),
 }
+
+impl RenderDocumentElement {
+    pub(crate) fn new(
+        config: &Config,
+        output_directory: &Path,
+        output_file: &Path,
+        original: &IDocumentElement,
+    ) -> Result<RenderDocumentElement, CustomError> {
+        match original {
+            IDocumentElement::Heading(inner) => Ok(RenderDocumentElement::Heading(
+                RenderHeading::new(config, output_directory, output_file, inner)?,
+            )),
+            IDocumentElement::Section(inner) => Ok(RenderDocumentElement::Section(
+                RenderSection::new(config, output_directory, output_file, inner)?,
+            )),
+        }
+    }
+}