Create base for future evaluators

src/main/kotlin/data/entity/Note.kt

@@ -1,6 +1,6 @@
-package data.model.entity
+package data.entity
 
-import data.model.enumeration.Pitch
+import data.enumeration.Pitch
 
 class Note private constructor(val pitch: Pitch, val octave: Int, val duration: Int, val dot: Boolean) {
     data class Builder(var pitch: Pitch = Pitch.A, var octave: Int = 4, var duration: Int = 4, var dot: Boolean = false) {

src/main/kotlin/data/enumeration/DataType.kt

@@ -0,0 +1,41 @@
+package data.enumeration
+
+import data.entity.Note
+import kotlin.reflect.KClass
+
+enum class DataType(val kotlinType: KClass<out Any>?) {
+    INT(Int::class),
+    FLOAT(Float::class),
+    STRING(String::class),
+    LIST(List::class),
+    MAP(Map::class),
+    NOTE(Note::class),
+    BOOL(Boolean::class),
+    TYPE(DataType::class),
+    VOID(null);
+
+    fun isInstance(value: Any?): Boolean {
+        if(kotlinType == null) {
+            return value == null
+        }
+
+        return kotlinType.isInstance(value)
+    }
+
+    override fun toString(): String {
+        return super.toString().toLowerCase()
+    }
+
+    companion object {
+        fun inference(value: Any?): DataType {
+            if (value == null) {
+                return VOID
+            }
+
+            return values()
+                .filter { it.kotlinType != null }
+                .find { it.kotlinType!!.isInstance(value) }
+                ?: throw RuntimeException("Cannot inference type for '$value'")
+        }
+    }
+}

src/main/kotlin/data/enumeration/Pitch.kt

@@ -1,6 +1,4 @@
-package data.model.enumeration
-
-import java.lang.RuntimeException
+package data.enumeration
 
 enum class Pitch {
     C, C_S, D, D_S, E, F, F_S, G, G_S, A, A_S, H;

src/main/kotlin/data/model/Value.kt

@@ -0,0 +1,67 @@
+package data.model
+
+import data.entity.Note
+import data.enumeration.DataType
+
+class Value private constructor(val type: DataType, val value: Any?, val properties: Map<String, Value> = emptyMap()) {
+    init {
+        if(!type.isInstance(value)) {
+            throw RuntimeException("'$value' is not of type $type")
+        }
+    }
+
+    override fun toString(): String {
+        return "$type($value)"
+    }
+
+    companion object {
+        fun int(value: Int): Value {
+            return Value(DataType.INT, value)
+        }
+
+        fun float(value: Float): Value {
+            return Value(DataType.FLOAT, value)
+        }
+
+        fun string(value: String): Value {
+            return Value(DataType.STRING, value, hashMapOf(
+                Pair("length", int(value.length))
+            ))
+        }
+
+        fun list(value: List<Value>): Value {
+            return Value(DataType.LIST, value, hashMapOf(
+                Pair("size", int(value.size))
+            ))
+        }
+
+        fun map(value: Map<Value, Value>): Value {
+            return Value(DataType.MAP, value, hashMapOf(
+                Pair("size", int(value.size)),
+                Pair("keys", list(value.keys.toList())),
+                Pair("values", list(value.values.toList()))
+            ))
+        }
+
+        fun note(value: Note): Value {
+            return Value(DataType.NOTE, value, hashMapOf(
+                Pair("pitch", string(value.pitch.toString())),
+                Pair("octave", int(value.octave)),
+                Pair("duration", int(value.duration)),
+                Pair("dot", bool(value.dot))
+            ))
+        }
+
+        fun bool(value: Boolean): Value {
+            return Value(DataType.BOOL, value)
+        }
+
+        fun type(value: DataType): Value {
+            return Value(DataType.TYPE, value)
+        }
+
+        fun void(): Value {
+            return Value(DataType.VOID, null)
+        }
+    }
+}

src/main/kotlin/dsl/ast/model/entity/ParserOutput.kt

@@ -3,7 +3,7 @@ package dsl.ast.model.entity
 import dsl.ast.model.enumeration.ParsingResult
 import dsl.ast.model.node.Node
 
-data class ParserOutput private constructor(val result: ParsingResult, val node: Node) {
+class ParserOutput private constructor(val result: ParsingResult, val node: Node) {
     fun map(mapper: (Node) -> Node): ParserOutput {
         return if(result == ParsingResult.OK) ok(mapper(node)) else fail()
     }

src/main/kotlin/dsl/token/tokenizer/NoteTokenizer.kt

@@ -1,7 +1,7 @@
 package dsl.token.tokenizer
 
-import data.model.entity.Note
-import data.model.enumeration.Pitch
+import data.entity.Note
+import data.enumeration.Pitch
 import dsl.token.model.entity.TokenizerOutput
 import dsl.token.model.enumeration.TokenType
 

src/main/kotlin/evaluation/environment/Environment.kt

@@ -0,0 +1,4 @@
+package evaluation.environment
+
+class Environment {
+}

src/main/kotlin/evaluation/evaluator/Evaluator.kt

@@ -0,0 +1,39 @@
+package evaluation.evaluator
+
+import dsl.ast.model.node.Node
+import evaluation.environment.Environment
+import evaluation.model.entity.EvaluatorOutput
+import evaluation.model.enumeration.EvaluationResult
+
+interface Evaluator {
+    fun evaluate(node: Node, environment: Environment): EvaluatorOutput
+
+    companion object {
+        fun forward(evaluator: Evaluator, vararg nodes: Node): Evaluator {
+            return object : Evaluator {
+                override fun evaluate(node: Node, environment: Environment): EvaluatorOutput {
+                    if(nodes.map { it::class }.any { it.isInstance(node) }) {
+                        return evaluator.evaluate(node, environment)
+                    }
+
+                    return EvaluatorOutput.fail()
+                }
+            }
+        }
+
+        fun oneOf(vararg evaluators: Evaluator): Evaluator {
+            return object : Evaluator {
+                override fun evaluate(node: Node, environment: Environment): EvaluatorOutput {
+                    for(evaluator in evaluators) {
+                        val output = evaluator.evaluate(node, environment)
+                        if(output.result != EvaluationResult.FAILED) {
+                            return output
+                        }
+                    }
+
+                    return EvaluatorOutput.fail()
+                }
+            }
+        }
+    }
+}

src/main/kotlin/evaluation/model/entity/EvaluatorOutput.kt

@@ -0,0 +1,20 @@
+package evaluation.model.entity
+
+import data.model.Value
+import evaluation.model.enumeration.EvaluationResult
+
+class EvaluatorOutput private constructor(val result: EvaluationResult, val value: Value?) {
+    companion object {
+        fun ok(): EvaluatorOutput {
+            return EvaluatorOutput(EvaluationResult.OK, null)
+        }
+
+        fun value(value: Value): EvaluatorOutput {
+            return EvaluatorOutput(EvaluationResult.VALUE, value)
+        }
+
+        fun fail(): EvaluatorOutput {
+            return EvaluatorOutput(EvaluationResult.FAILED, null)
+        }
+    }
+}

src/main/kotlin/evaluation/model/enumeration/EvaluationResult.kt

@@ -0,0 +1,7 @@
+package evaluation.model.enumeration
+
+enum class EvaluationResult {
+    OK,
+    VALUE,
+    FAILED
+}