Json utils

json/json.mbt

@@ -0,0 +1,330 @@
+// Copyright 2024 International Digital Economy Academy
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+/// Try to get this element as a Null
+pub fn as_null(self : JsonValue) -> Option[Unit] {
+  match self {
+    Null => Some(())
+    _ => None
+  }
+}
+
+test "get as null" {
+  inspect(JsonValue::Null |> as_null, content="Some(())")?
+  inspect(JsonValue::Boolean(false) |> as_null, content="None")?
+  inspect(JsonValue::Number(1.0) |> as_null, content="None")?
+  inspect(JsonValue::String("Hello World") |> as_null, content="None")?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")]) |> as_null,
+    content="None",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    )
+    |> as_null,
+    content="None",
+  )?
+}
+
+/// Try to get this element as a Boolean
+pub fn as_bool(self : JsonValue) -> Option[Bool] {
+  match self {
+    Boolean(b) => Some(b)
+    _ => None
+  }
+}
+
+test "get as bool" {
+  inspect(JsonValue::Null |> as_bool, content="None")?
+  inspect(JsonValue::Boolean(false) |> as_bool, content="Some(false)")?
+  inspect(JsonValue::Number(1.0) |> as_bool, content="None")?
+  inspect(JsonValue::String("Hello World") |> as_bool, content="None")?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")]) |> as_bool,
+    content="None",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    )
+    |> as_bool,
+    content="None",
+  )?
+}
+
+/// Try to get this element as a Number
+pub fn as_number(self : JsonValue) -> Option[Double] {
+  match self {
+    Number(n) => Some(n)
+    _ => None
+  }
+}
+
+test "get as number" {
+  inspect(JsonValue::Null |> as_number, content="None")?
+  inspect(JsonValue::Boolean(false) |> as_number, content="None")?
+  inspect(JsonValue::Number(1.0) |> as_number, content="Some(1.0)")?
+  inspect(JsonValue::String("Hello World") |> as_number, content="None")?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")]) |> as_number,
+    content="None",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    )
+    |> as_number,
+    content="None",
+  )?
+}
+
+/// Try to get this element as a String
+pub fn as_string(self : JsonValue) -> Option[String] {
+  match self {
+    String(s) => Some(s)
+    _ => None
+  }
+}
+
+test "get as string" {
+  inspect(JsonValue::Null |> as_string, content="None")?
+  inspect(JsonValue::Boolean(false) |> as_string, content="None")?
+  inspect(JsonValue::Number(1.0) |> as_string, content="None")?
+  inspect(
+    JsonValue::String("Hello World") |> as_string,
+    content="Some(Hello World)",
+  )?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")]) |> as_string,
+    content="None",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    )
+    |> as_string,
+    content="None",
+  )?
+}
+
+/// Try to get this element as an Array
+pub fn as_array(self : JsonValue) -> Option[@vec.Vec[JsonValue]] {
+  match self {
+    Array(arr) => Some(arr)
+    _ => None
+  }
+}
+
+/// Try to get this element as a Json Array and get the element at the `index` as a Json Value
+pub fn item(self : JsonValue, index : Int) -> Option[JsonValue] {
+  self.as_array()?.get(index)
+}
+
+test "get as array" {
+  inspect(JsonValue::Null |> as_array, content="None")?
+  inspect(JsonValue::Boolean(false) |> as_array, content="None")?
+  inspect(JsonValue::Number(1.0) |> as_array, content="None")?
+  inspect(JsonValue::String("Hello World") |> as_array, content="None")?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")]) |> as_array,
+    content="Some(Vec::[String(\"Hello World\")])",
+  )?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")]).item(0).bind(
+      as_string,
+    ),
+    content="Some(Hello World)",
+  )?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")]).item(1).bind(
+      as_string,
+    ),
+    content="None",
+  )?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")]).item(0).bind(
+      as_number,
+    ),
+    content="None",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    )
+    |> as_array,
+    content="None",
+  )?
+}
+
+/// Try to get this element as an Object
+pub fn as_object(self : JsonValue) -> Option[@map.Map[String, JsonValue]] {
+  match self {
+    Object(obj) => Some(obj)
+    _ => None
+  }
+}
+
+/// Try to get this element as a Json Object and get the element with the `key` as a Json Value
+pub fn value(self : JsonValue, key : String) -> Option[JsonValue] {
+  self.as_object()?.lookup(key)
+}
+
+test "get as object" {
+  inspect(
+    JsonValue::Null |> as_object |> Option::map(@map.Map::to_vec),
+    content="None",
+  )?
+  inspect(
+    JsonValue::Boolean(false) |> as_object |> Option::map(@map.Map::to_vec),
+    content="None",
+  )?
+  inspect(
+    JsonValue::Number(1.0) |> as_object |> Option::map(@map.Map::to_vec),
+    content="None",
+  )?
+  inspect(
+    JsonValue::String("Hello World")
+    |> as_object
+    |> Option::map(@map.Map::to_vec),
+    content="None",
+  )?
+  inspect(
+    JsonValue::Array(@vec.Vec::[JsonValue::String("Hello World")])
+    |> as_object
+    |> Option::map(@map.Map::to_vec),
+    content="None",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    )
+    |> as_object
+    |> Option::map(@map.Map::to_vec),
+    content="Some(Vec::[(key, String(\"key\")), (value, Number(100.0))])",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    ).value("key").bind(as_string),
+    content="Some(key)",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    ).value("value").bind(as_number),
+    content="Some(100.0)",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    ).value("key").bind(as_number),
+    content="None",
+  )?
+  inspect(
+    JsonValue::Object(
+      @map.Map::[
+        ("key", JsonValue::String("key")),
+        ("value", JsonValue::Number(100.0)),
+      ],
+    ).value("asdf").bind(as_number),
+    content="None",
+  )?
+}
+
+test "deep access" {
+  let json = JsonValue::Object(
+    @map.Map::[
+      (
+        "key",
+        JsonValue::Array(
+          @vec.Vec::[
+            JsonValue::Number(1.0),
+            JsonValue::Boolean(true),
+            JsonValue::Null,
+            JsonValue::Array(@vec.Vec::[]),
+            JsonValue::Object(
+              @map.Map::[
+                ("key", JsonValue::String("value")),
+                ("value", JsonValue::Number(100.0)),
+              ],
+            ),
+          ],
+        ),
+      ),
+      ("null", JsonValue::Null),
+      ("bool", JsonValue::Boolean(false)),
+      ("obj", JsonValue::Object(@map.Map::[])),
+    ],
+  )
+  inspect(json.value("null").bind(as_null), content="Some(())")?
+  inspect(
+    json.value("key").bind(fn { array => array.item(2) }).bind(as_null),
+    content="Some(())",
+  )?
+  inspect(json.value("bool").bind(as_bool), content="Some(false)")?
+  inspect(
+    json.value("key").bind(fn { array => array.item(1) }).bind(as_bool),
+    content="Some(true)",
+  )?
+  inspect(
+    json.value("key").bind(as_array),
+    content="Some(Vec::[Number(1.0), Boolean(true), Null, Array(Vec::[]), Object(Map::[(\"key\", String(\"value\")), (\"value\", Number(100.0))])])",
+  )?
+  inspect(
+    json.value("key").bind(fn { array => array.item(3) }).bind(as_array),
+    content="Some(Vec::[])",
+  )?
+  inspect(
+    json.value("key").bind(fn { array => array.item(4) }).bind(as_object).map(
+      @map.Map::to_vec,
+    ),
+    content="Some(Vec::[(key, String(\"value\")), (value, Number(100.0))])",
+  )?
+  inspect(
+    json.value("obj").bind(as_object).map(@map.Map::to_vec),
+    content="Some(Vec::[])",
+  )?
+  inspect(
+    (fn() { json.value("key")?.item(4)?.value("value")?.as_number() })(),
+    content="Some(100.0)",
+  )?
+}

json/json.mbti

@@ -14,9 +14,17 @@ pub enum JsonValue {
   Array(@vec.Vec[JsonValue])
   Object(@map.Map[String, JsonValue])
 }
+fn JsonValue::as_array(JsonValue) -> Option[@vec.Vec[JsonValue]]
+fn JsonValue::as_bool(JsonValue) -> Option[Bool]
+fn JsonValue::as_null(JsonValue) -> Option[Unit]
+fn JsonValue::as_number(JsonValue) -> Option[Double]
+fn JsonValue::as_object(JsonValue) -> Option[@map.Map[String, JsonValue]]
+fn JsonValue::as_string(JsonValue) -> Option[String]
 fn JsonValue::debug_write(JsonValue, Buffer) -> Unit
+fn JsonValue::item(JsonValue, Int) -> Option[JsonValue]
 fn JsonValue::op_equal(JsonValue, JsonValue) -> Bool
 fn JsonValue::to_string(JsonValue) -> String
+fn JsonValue::value(JsonValue, String) -> Option[JsonValue]
 
 // Traits
 

json/moon.pkg.json

@@ -1,12 +1,16 @@
 {
-    "import": [
-        "moonbitlang/core/builtin",
-        "moonbitlang/core/double",
-        "moonbitlang/core/string",
-        "moonbitlang/core/bool",
-        "moonbitlang/core/tuple",
-        "moonbitlang/core/vec",
-        "moonbitlang/core/map",
-        "moonbitlang/core/coverage"
-    ]
-}
+  "import": [
+    "moonbitlang/core/builtin",
+    "moonbitlang/core/double",
+    "moonbitlang/core/string",
+    "moonbitlang/core/bool",
+    "moonbitlang/core/tuple",
+    "moonbitlang/core/vec",
+    "moonbitlang/core/map",
+    "moonbitlang/core/coverage",
+    "moonbitlang/core/assertion",
+    "moonbitlang/core/int",
+    "moonbitlang/core/unit",
+    "moonbitlang/core/option"
+  ]
+}