Implement footnote reference.

src/wasm/footnote_reference.rs

@@ -4,15 +4,16 @@ use serde::Serialize;
 use super::ast_node::WasmAstNode;
 use super::macros::to_wasm;
 use super::to_wasm::ToWasm;
-use super::AdditionalProperties;
 use crate::compare::ElispFact;
 use crate::types::FootnoteReference;
+use crate::types::FootnoteReferenceType;
 use crate::wasm::to_wasm::ToWasmStandardProperties;
 
 #[derive(Debug, Serialize, Deserialize)]
 pub struct WasmFootnoteReference {
-    #[serde(flatten)]
+    pub(crate) label: Option<String>,
-    pub(crate) additional_properties: AdditionalProperties,
+    #[serde(rename = "type")]
+    pub(crate) footnote_reference_type: String,
 }
 
 to_wasm!(
@@ -21,12 +22,27 @@ to_wasm!(
     original,
     wasm_context,
     { WasmAstNode::FootnoteReference(original) },
-    { "TODO".into() },
+    { "footnote-reference".into() },
     {
+        let children = original
+            .definition
+            .iter()
+            .map(|child| {
+                child
+                    .to_wasm(wasm_context.clone())
+                    .map(Into::<WasmAstNode>::into)
+            })
+            .collect::<Result<Vec<_>, _>>()?;
+
         Ok((
-            Vec::new(),
+            children,
             WasmFootnoteReference {
-                additional_properties: AdditionalProperties::default(),
+                label: original.label.map(|s| s.to_owned()),
+                footnote_reference_type: match original.get_type() {
+                    FootnoteReferenceType::Standard => "standard",
+                    FootnoteReferenceType::Inline => "inline",
+                }
+                .to_owned(),
             },
         ))
     }