chore(docs): Add examples to Marshal module (#2014)

Co-authored-by: Blaine Bublitz <blaine.bublitz@gmail.com>

stdlib/marshal.gr

@@ -3,6 +3,10 @@
  *
  * @example from "marshal" include Marshal
  *
+ * @example Marshal.marshal(1)
+ * @example Marshal.marshal("Hello World")
+ * @example Marshal.unmarshal(b"\x03\x00\x00\x00")
+ *
  * @since v0.5.3
  */
 module Marshal
@@ -418,6 +422,9 @@ let marshal = (value, buf) => {
  * @param value: The value to serialize
  * @returns A byte-based representation of the value
  *
+ * @example Marshal.marshal(1) == b"\x03\x00\x00\x00"
+ * @example Marshal.marshal("🌾") == Marshal.marshal("🌾")
+ *
  * @since v0.5.3
  */
 @unsafe
@@ -1047,6 +1054,9 @@ let unmarshal = buf => {
  * @param bytes: The data to deserialize
  * @returns An in-memory value
  *
+ * @example Marshal.unmarshal(Marshal.marshal('🌾')) == Ok('🌾')
+ * @example Marshal.unmarshal(b"\x03\x00\x00\x00") == Ok(1)
+ *
  * @since v0.5.3
  */
 @unsafe

stdlib/marshal.md

@@ -13,6 +13,18 @@ No other changes yet.
 from "marshal" include Marshal
 ```
 
+```grain
+Marshal.marshal(1)
+```
+
+```grain
+Marshal.marshal("Hello World")
+```
+
+```grain
+Marshal.unmarshal(b"\x03\x00\x00\x00")
+```
+
 ## Values
 
 Functions and constants included in the Marshal module.
@@ -44,6 +56,16 @@ Returns:
 |----|-----------|
 |`Bytes`|A byte-based representation of the value|
 
+Examples:
+
+```grain
+Marshal.marshal(1) == b"\x03\x00\x00\x00"
+```
+
+```grain
+Marshal.marshal("🌾") == Marshal.marshal("🌾")
+```
+
 ### Marshal.**unmarshal**
 
 <details disabled>
@@ -74,3 +96,13 @@ Returns:
 |----|-----------|
 |`Result<a, String>`|An in-memory value|
 
+Examples:
+
+```grain
+Marshal.unmarshal(Marshal.marshal('🌾')) == Ok('🌾')
+```
+
+```grain
+Marshal.unmarshal(b"\x03\x00\x00\x00") == Ok(1)
+```
+