[WIP] update & sample

Author: patjackson52

build.gradle

@@ -1,5 +1,10 @@
+apply from: "$rootDir/gradle/dependencies.gradle"
+
 buildscript {
     apply from: "$rootDir/gradle/dependencies.gradle"
+    ext {
+        kotlin_version = '1.3.70'
+    }
 
     repositories {
         google()
@@ -12,9 +17,10 @@ buildscript {
     dependencies {
         classpath deps.plugins.kotlin
         classpath deps.plugins.dokka
+//        classpath deps.plugins.android
+        classpath 'com.android.tools.build:gradle:3.6.0'
     }
 }
-apply from: "$rootDir/gradle/dependencies.gradle"
 
 allprojects {
     repositories {

gradle/dependencies.gradle

@@ -2,12 +2,14 @@ ext.versions = [
         kotlin          : '1.3.70',
         dokka           : '0.9.17',
         spek            : '2.1.0-alpha.0.9+3d5d865',
-        atrium          : '0.8.0'
+        atrium          : '0.8.0',
+        androidBuildTools : '3.6.1'
 ]
 
 ext.deps = [
         plugins: [
                 kotlin : "org.jetbrains.kotlin:kotlin-gradle-plugin:${versions.kotlin}",
                 dokka  : "org.jetbrains.dokka:dokka-gradle-plugin:${versions.dokka}",
+                android : "com.android.tools.build:${versions.androidBuildTools}"
         ]
 ]

lib/src/commonMain/kotlin/org/reduxkotlin/Reselect.kt

@@ -2,7 +2,8 @@ package org.reduxkotlin
 
 import kotlin.jvm.JvmField
 
-private typealias EqualityCheckFn = (a:Any,b:Any)->Boolean
+private typealias EqualityCheckFn = (a:Any, b:Any) -> Boolean
+
 /**
  * A rewrite for kotlin of https://github.com/reactjs/reselect library for redux (https://github.com/reactjs/redux)
  * see also "Computing Derived Data" in redux documentation http://redux.js.org/docs/recipes/ComputingDerivedData.html
@@ -18,13 +19,6 @@ val byRefEqualityCheck: EqualityCheckFn = { a: Any, b: Any -> a === b }
  */
 val byValEqualityCheck: EqualityCheckFn = { a: Any, b: Any -> a == b }
 
-/**
- * a class for keeping a non null object reference even when actual reference is null
- * Needed because selectors do not work for nullable fields: if you have a field in the state that is
- * nullable T? the define instead as Opt<T> if you want selectors to work
- */
-class Opt<T>(@JvmField val it:T?)
-
 interface Memoizer<T> {
     fun memoize(state: Any, vararg inputs: SelectorInput<Any, Any>): T
 }
@@ -114,24 +108,6 @@ interface Selector<S, O> : SelectorInput<S, O> {
         getIfChangedIn(state)?.let(blockfn)
     }
 
-    /**
-     * same as regular [onChangeIn] but don't activate selector unless [condition] is true
-     * Note that the selector is not run at all if [condition] is false. Therefore
-     * the selector will be triggered by changes that happened and where ignored, as soon as
-     * [condition] become true
-     */
-    fun onChangeIn(state: S, condition:Boolean,blockfn: (O) -> Unit) {
-        if(condition) getIfChangedIn(state)?.let(blockfn)
-    }
-}
-
-/**
- * same as [Selector.onChangeIn], but as extension function of state:
- * it checks if the specified selector value  is changed for the input state and if so, call [blockfn]
- * with the updated selector value
- */
-fun <S,O> S.whenChangeOf(selector: Selector<S, O>, blockfn: (O) -> Unit) {
-    selector.getIfChangedIn(this)?.let(blockfn)
 }
 
 /**
@@ -164,156 +140,12 @@ abstract class AbstractSelector<S, O> : Selector<S, O> {
 
 }
 
-//use @JvmField annotation for avoiding generation useless getter methods
-class SelectorForP5<S:Any, I0 : Any, I1 : Any, I2 : Any, I3 : Any, I4 : Any>(@JvmField val si0: SelectorInput<S, I0>,
-                                                                             @JvmField val si1: SelectorInput<S, I1>,
-                                                                             @JvmField val si2: SelectorInput<S, I2>,
-                                                                             @JvmField val si3: SelectorInput<S, I3>,
-                                                                             @JvmField val si4: SelectorInput<S, I4>
-) {
-    fun<O> compute(equalityCheckForResult: EqualityCheckFn = byRefEqualityCheck, computeFun: (I0, I1, I2, I3, I4) -> O) = object : AbstractSelector<S, O>() {
-        override val equalityCheck: EqualityCheckFn
-            get() = equalityCheckForResult
-        override val computeAndCount = fun(i: Array<out Any>): O {
-            ++_recomputations
-            @Suppress("UNCHECKED_CAST")
-            return computeFun(i[0] as I0, i[1] as I1, i[2] as I2, i[3] as I3, i[4] as I4)
-        }
-
-        override operator fun invoke(state: S): O {
-            @Suppress("UNCHECKED_CAST")
-            return memoizer.memoize(
-                   state,
-                    si0 as SelectorInput<Any, Any>,
-                    si1 as SelectorInput<Any, Any>,
-                    si2 as SelectorInput<Any, Any>,
-                    si3 as SelectorInput<Any, Any>,
-                    si4 as SelectorInput<Any, Any>
-            )
-        }
-    }
-}
-
-//use @JvmField annotation for avoiding generation useless getter methods
-class SelectorForP4<S:Any, I0 : Any, I1 : Any, I2 : Any, I3 : Any>(@JvmField val si0: SelectorInput<S, I0>,
-                                                                   @JvmField val si1: SelectorInput<S, I1>,
-                                                                   @JvmField val si2: SelectorInput<S, I2>,
-                                                                   @JvmField val si3: SelectorInput<S, I3>
-) {
-    fun<I4 : Any> withField(fn: S.() -> I4) = SelectorForP5<S, I0, I1, I2, I3, I4>(si0, si1, si2, si3, InputField(fn, byRefEqualityCheck))
-    fun<I4 : Any> withFieldByValue(fn: S.() -> I4) = SelectorForP5<S, I0, I1, I2, I3, I4>(si0, si1, si2, si3, InputField(fn, byValEqualityCheck))
-    fun<I4 : Any> withSelector(si: SelectorInput<S, I4>) = SelectorForP5<S, I0, I1, I2, I3, I4>(si0, si1, si2, si3, si)
-    fun<O> compute(equalityCheckForResult: EqualityCheckFn = byRefEqualityCheck, computeFun: (I0, I1, I2, I3) -> O) = object : AbstractSelector<S, O>() {
-        override val equalityCheck: EqualityCheckFn
-            get() = equalityCheckForResult
-        override val computeAndCount = fun(i: Array<out Any>): O {
-            ++_recomputations
-            @Suppress("UNCHECKED_CAST")
-            return computeFun(i[0] as I0, i[1] as I1, i[2] as I2, i[3] as I3)
-        }
-
-        override operator fun invoke(state: S): O {
-            @Suppress("UNCHECKED_CAST")
-            return memoizer.memoize(
-                    state,
-                    si0 as SelectorInput<Any, Any>,
-                    si1 as SelectorInput<Any, Any>,
-                    si2 as SelectorInput<Any, Any>,
-                    si3 as SelectorInput<Any, Any>
-            )
-        }
-    }
-}
-
-//use @JvmField annotation for avoiding generation useless getter methods
-class SelectorForP3<S:Any, I0 : Any, I1 : Any, I2 : Any>(@JvmField val si0: SelectorInput<S, I0>,
-                                                         @JvmField val si1: SelectorInput<S, I1>,
-                                                         @JvmField val si2: SelectorInput<S, I2>
-) {
-    fun<I3 : Any> withField(fn: S.() -> I3) = SelectorForP4(si0, si1, si2, InputField(fn, byRefEqualityCheck))
-    fun<I3 : Any> withFieldByValue(fn: S.() -> I3) = SelectorForP4(si0, si1, si2, InputField(fn, byValEqualityCheck))
-    fun<I3 : Any> withSelector(si: SelectorInput<S, I3>) = SelectorForP4(si0, si1, si2, si)
-    fun<O> compute(equalityCheckForResult: EqualityCheckFn = byRefEqualityCheck, computeFun: (I0, I1, I2) -> O) = object : AbstractSelector<S, O>() {
-        override val equalityCheck: EqualityCheckFn
-            get() = equalityCheckForResult
-        override val computeAndCount = fun(i: Array<out Any>): O {
-            ++_recomputations
-            @Suppress("UNCHECKED_CAST")
-            return computeFun(i[0] as I0, i[1] as I1, i[2] as I2)
-        }
-
-        override operator fun invoke(state: S): O {
-            @Suppress("UNCHECKED_CAST")
-            return memoizer.memoize(
-                    state,
-                    si0 as SelectorInput<Any, Any>,
-                    si1 as SelectorInput<Any, Any>,
-                    si2 as SelectorInput<Any, Any>
-            )
-        }
-    }
-}
-
-//use @JvmField annotation for avoiding generation useless getter methods
-class SelectorForP2<S:Any, I0 : Any, I1 : Any>(@JvmField val si0: SelectorInput<S, I0>,
-                                               @JvmField val si1: SelectorInput<S, I1>
-) {
-    fun<I2 : Any> withField(fn: S.() -> I2) = SelectorForP3<S, I0, I1, I2>(si0, si1, InputField(fn, byRefEqualityCheck))
-    fun<I2 : Any> withFieldByValue(fn: S.() -> I2) = SelectorForP3<S, I0, I1, I2>(si0, si1, InputField(fn, byValEqualityCheck))
-    fun<I2 : Any> withSelector(si: SelectorInput<S, I2>) = SelectorForP3<S, I0, I1, I2>(si0, si1, si)
-    fun<O> compute(equalityCheckForResult: EqualityCheckFn = byRefEqualityCheck, computeFun: (I0, I1) -> O) = object : AbstractSelector<S, O>() {
-        override val equalityCheck: EqualityCheckFn
-            get() = equalityCheckForResult
-        override val computeAndCount = fun(i: Array<out Any>): O {
-            ++_recomputations
-            @Suppress("UNCHECKED_CAST")
-            return computeFun(i[0] as I0, i[1] as I1)
-        }
-
-        override operator fun invoke(state: S): O {
-            @Suppress("UNCHECKED_CAST")
-            return memoizer.memoize(
-                    state,
-                    si0 as SelectorInput<Any, Any>,
-                    si1 as SelectorInput<Any, Any>
-            )
-        }
-    }
-}
-
-//use @JvmField annotation for avoiding generation useless getter methods
-class SelectorForP1<S:Any, I0 : Any>(@JvmField val si0: SelectorInput<S, I0>) {
-    fun<I1 : Any> withField(fn: S.() -> I1) = SelectorForP2<S, I0, I1>(si0, InputField(fn, byRefEqualityCheck))
-    fun<I1 : Any> withFieldByValue(fn: S.() -> I1) = SelectorForP2<S, I0, I1>(si0, InputField(fn, byValEqualityCheck))
-    fun<I1 : Any> withSelector(si: SelectorInput<S, I1>) = SelectorForP2<S, I0, I1>(si0, si)
-    fun<O> compute(equalityCheckForResult: EqualityCheckFn = byRefEqualityCheck, computeFun: (I0) -> O) = object : AbstractSelector<S, O>() {
-        override val equalityCheck: EqualityCheckFn
-            get() = equalityCheckForResult
-        override val computeAndCount = fun(i: Array<out Any>): O {
-            ++_recomputations
-            @Suppress("UNCHECKED_CAST")
-            return computeFun(i[0] as I0)
-        }
-
-        override operator fun invoke(state: S): O {
-            @Suppress("UNCHECKED_CAST")
-            return memoizer.memoize(
-                    state,
-                    si0 as SelectorInput<Any, Any>
-            )
-        }
-    }
-}
 
 /**
  * wrapper class for Selector factory methods , that basically is used only to capture
  * type information for the state parameter
  */
 class SelectorBuilder<S:Any> {
-    fun<I0 : Any> withField(fn: S.() -> I0) = SelectorForP1<S, I0>(InputField(fn, byRefEqualityCheck))
-    fun<I0 : Any> withFieldByValue(fn: S.() -> I0) = SelectorForP1<S, I0>(InputField(fn, byValEqualityCheck))
-    fun<I0 : Any> withSelector(si: SelectorInput<S, I0>) = SelectorForP1<S, I0>(si)
-
     /**
      * special single input selector that should be used when you just want to retrieve a single field:
      * Warning: Don't use this with primitive type fields, use [withSingleFieldByValue] instead!!!
@@ -363,5 +195,38 @@ class SelectorBuilder<S:Any> {
     }
 }
 
+/**
+ * Helper function that creates a DSL for subscribing to changes in specific state fields and actions to take.
+ * Inside the lambda there is access to the current state through the var `state`
+ *
+ * ex:
+ *      val sel = selectorSubscriberFn {
+ *          select({it.foo}, { actionWhenFooChanges() }
+ *
+ *          withAnyChange {
+ *              //called whenever any change happens to state
+ *              view.setMessage(state.barMsg) //state is current state
+ *          }
+ *      }
+ */
+fun <State: Any>Store<State>.selectors(selectorSubscriberBuilderInit: SelectorSubscriberBuilder<State>.() -> Unit): StoreSubscriber {
+    val subscriberBuilder: SelectorSubscriberBuilder<State> = SelectorSubscriberBuilder(this)
+    subscriberBuilder.selectorSubscriberBuilderInit()
+    val sub = {
+        subscriberBuilder.selectorList.forEach { entry ->
+            @Suppress("UNCHECKED_CAST")
+            (entry.key as Selector<State, *>).onChangeIn(getState()) { entry.value(getState()) }
+        }
+        subscriberBuilder.withAnyChangeFun?.invoke()
+        Unit
+    }
+    //call subscriber immediately when subscribing
+    sub()
+    return this.subscribe(sub)
+}
 
-
+fun <State: Any>Store<State>.select(selector: (State) -> Any, action: (Any) -> Unit): StoreSubscriber {
+    return subscribe(this.selectors {
+        select(selector, action)
+    })
+}

lib/src/commonMain/kotlin/org/reduxkotlin/SelectorSubscriberBuilder.kt

@@ -1,6 +1,5 @@
 package org.reduxkotlin
 
-
 /**
  * A Selector Subscriber - group of selectors that subscribe to store state changes.
  *
@@ -22,31 +21,9 @@ class SelectorSubscriberBuilder<State : Any>(val store: Store<State>) {
         withAnyChangeFun = f
     }
 
-
-    fun withSingleField(selector: (State) -> Any, action: (Any) -> Unit) {
+    fun select(selector: (State) -> Any, action: (Any) -> Unit) {
         val selBuilder = SelectorBuilder<State>()
         val sel = selBuilder.withSingleField(selector)
         selectorList[sel] = action
     }
-
-    infix fun SelectorSubscriberBuilder<State>.select(selector: (State) -> Any): AbstractSelector<State, Any> =
-            SelectorBuilder<State>().withSingleField(selector)
-
-    infix fun SelectorSubscriberBuilder<State>.on(selector: (State) -> Any): AbstractSelector<State, Any> =
-            SelectorBuilder<State>().withSingleField(selector)
-
-    operator fun (() -> Any).unaryPlus(): AbstractSelector<State, Any> {
-        val that = this
-        return SelectorBuilder<State>().withSingleField { that() }
-    }
-
-    infix fun AbstractSelector<State, Any>.then(action: (Any) -> Unit) {
-        selectorList[this] = action
-    }
-
-    infix operator fun AbstractSelector<State, Any>.plus(action: (Any) -> Unit) {
-        selectorList[this] = action
-    }
 }
-
-

sample/.gitignore

@@ -0,0 +1 @@
+/build

sample/build.gradle

@@ -0,0 +1,56 @@
+apply plugin: 'com.android.application'
+apply plugin: 'kotlin-android'
+apply plugin: 'kotlin-android-extensions'
+
+android {
+    compileSdkVersion 29
+    buildToolsVersion "29.0.2"
+
+    defaultConfig {
+        applicationId "org.reduxkotlin.reselect.sample"
+        minSdkVersion 21
+        targetSdkVersion 29
+        versionCode 1
+        versionName "1.0"
+
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
+    }
+
+// To inline the bytecode built with JVM target 1.8 into
+// bytecode that is being built with JVM target 1.6. (e.g. navArgs)
+
+
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+    kotlinOptions {
+        jvmTarget = "1.8"
+    }
+
+}
+
+dependencies {
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
+    implementation 'androidx.appcompat:appcompat:1.1.0'
+    implementation 'androidx.core:core-ktx:1.2.0'
+    implementation 'com.google.android.material:material:1.1.0'
+    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'
+    implementation 'androidx.navigation:navigation-fragment-ktx:2.2.1'
+    implementation 'androidx.navigation:navigation-ui-ktx:2.2.1'
+    implementation 'org.reduxkotlin:redux-kotlin:0.4.0'
+    implementation 'org.reduxkotlin:redux-kotlin-thunk:0.4.0'
+    implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-android:1.3.3'
+    implementation project(':lib')
+    testImplementation 'junit:junit:4.13'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
+}