Update README.md and examples

Signed-off-by: Glenn Lewis <6598971+gmlewis@users.noreply.github.com>

README.md

@@ -34,11 +34,15 @@ You can find the reference documentation for this library on [mooncakes.io]:
 
 Examples can also be found there:
 
+* [extism/moonbit-pdk/examples/add]
+* [extism/moonbit-pdk/examples/arrays]
 * [extism/moonbit-pdk/examples/count-vowels]
 * [extism/moonbit-pdk/examples/greet]
 * [extism/moonbit-pdk/examples/http-get]
 * [extism/moonbit-pdk/examples/kitchen-sink]
 
+[extism/moonbit-pdk/examples/add]: https://mooncakes.io/docs/#/extism/moonbit-pdk/examples/add/members
+[extism/moonbit-pdk/examples/arrays]: https://mooncakes.io/docs/#/extism/moonbit-pdk/examples/arrays/members
 [extism/moonbit-pdk/examples/count-vowels]: https://mooncakes.io/docs/#/extism/moonbit-pdk/examples/count-vowels/members
 [extism/moonbit-pdk/examples/greet]: https://mooncakes.io/docs/#/extism/moonbit-pdk/examples/greet/members
 [extism/moonbit-pdk/examples/http-get]: https://mooncakes.io/docs/#/extism/moonbit-pdk/examples/http-get/members
@@ -91,7 +95,6 @@ and include the `@host` import into your plugin:
 
 ```json
 {
-  "is-main": true,
   "import": [
     "extism/moonbit-pdk/pdk/host"
   ],
@@ -175,44 +178,53 @@ struct Add {
 }
 
 pub fn Add::from_json(value : @json.JsonValue) -> Add? {
-  let value = value.as_object()?
-  let a = value.get("a")?.as_number()
-  let b = value.get("b")?.as_number()
+  let value = match value.as_object() {
+    Some(v) => v
+    _ => return None
+  }
+  let a = match value.get("a") {
+    Some(v) => v
+    _ => return None
+  }
+  let a = a.as_number()
+  let b = match value.get("b") {
+    Some(v) => v
+    _ => return None
+  }
+  let b = b.as_number()
   match (a, b) {
     (Some(a), Some(b)) => Some({ a: a.to_int(), b: b.to_int() })
     _ => None
   }
 }
 
-pub fn Add::parse(s : String) -> Add!String {
-  match @json.parse(s)!! {
+type! ParseError String derive(Show)
+
+pub fn Add::parse(s : String) -> Add!ParseError {
+  match @json.parse?(s) {
     Ok(jv) =>
       match Add::from_json(jv) {
         Some(value) => value
-        None => {
-          raise "unable to parse Add \{s}"
-        }
+        None => raise ParseError("unable to parse Add \{s}")
       }
-    Err(e) => {
-      raise "unable to parse Add \{s}: \{e}"
-    }
+    Err(e) => raise ParseError("unable to parse Add \{s}: \{e}")
   }
 }
 
 struct Sum {
   sum : Int
 }
 
-pub fn to_json(self: Sum) -> Json {
+pub fn to_json(self : Sum) -> Json {
   { "sum": self.sum.to_json() }
 }
 
 pub fn add() -> Int {
   let input = @host.input_string()
   let params = try {
-    Add::parse(input)!
+    Add::parse!(input)
   } catch {
-    e => {
+    ParseError(e) => {
       @host.set_error(e)
       return 1
     }
@@ -230,7 +242,6 @@ Export your `add` function in `main/moon.pkg.json`:
 
 ```json
 {
-  "is-main": true,
   "import": [
     "extism/moonbit-pdk/pdk/host"
   ],
@@ -281,7 +292,6 @@ export your function:
 
 ```json
 {
-  "is-main": true,
   "import": [
     "extism/moonbit-pdk/pdk/config",
     "extism/moonbit-pdk/pdk/host"
@@ -335,7 +345,6 @@ export your function:
 
 ```json
 {
-  "is-main": true,
   "import": [
     "extism/moonbit-pdk/pdk/host",
     "extism/moonbit-pdk/pdk/var"

examples/add/README.md

@@ -0,0 +1,10 @@
+# examples/add
+
+The `add.wasm` plugin can be run from the top-level of the repo by
+typing:
+
+```bash
+$ ./build.sh
+$ ./scripts/add.sh '{"a": 20, "b": 21}'
+# => {"sum":41}
+```

examples/add/add.mbt

@@ -0,0 +1,63 @@
+struct Add {
+  a : Int
+  b : Int
+}
+
+pub fn Add::from_json(value : @json.JsonValue) -> Add? {
+  let value = match value.as_object() {
+    Some(v) => v
+    _ => return None
+  }
+  let a = match value.get("a") {
+    Some(v) => v
+    _ => return None
+  }
+  let a = a.as_number()
+  let b = match value.get("b") {
+    Some(v) => v
+    _ => return None
+  }
+  let b = b.as_number()
+  match (a, b) {
+    (Some(a), Some(b)) => Some({ a: a.to_int(), b: b.to_int() })
+    _ => None
+  }
+}
+
+type! ParseError String derive(Show)
+
+pub fn Add::parse(s : String) -> Add!ParseError {
+  match @json.parse?(s) {
+    Ok(jv) =>
+      match Add::from_json(jv) {
+        Some(value) => value
+        None => raise ParseError("unable to parse Add \{s}")
+      }
+    Err(e) => raise ParseError("unable to parse Add \{s}: \{e}")
+  }
+}
+
+struct Sum {
+  sum : Int
+}
+
+pub fn to_json(self : Sum) -> Json {
+  { "sum": self.sum.to_json() }
+}
+
+pub fn add() -> Int {
+  let input = @host.input_string()
+  let params = try {
+    Add::parse!(input)
+  } catch {
+    ParseError(e) => {
+      @host.set_error(e)
+      return 1
+    }
+  }
+  //
+  let sum = { sum: params.a + params.b }
+  let json_value = sum.to_json()
+  @host.output_json_value(json_value)
+  0 // success
+}

examples/add/moon.pkg.json

@@ -0,0 +1,13 @@
+{
+  "import": [
+    "extism/moonbit-pdk/pdk/host"
+  ],
+  "link": {
+    "wasm": {
+      "exports": [
+        "add"
+      ],
+      "export-memory-name": "memory"
+    }
+  }
+}

moon.mod.json

@@ -1,6 +1,6 @@
 {
   "name": "extism/moonbit-pdk",
-  "version": "0.36.0",
+  "version": "0.37.0",
   "deps": {},
   "readme": "README.md",
   "repository": "https://github.com/extism/moonbit-pdk",

scripts/add.sh

@@ -0,0 +1,2 @@
+#!/bin/bash -ex
+extism call target/wasm/release/build/examples/add/add.wasm add --wasi --input "$@"