Make assertion that enables throwing only strings with 'throw' statement

app/src/main/kotlin/io/smnp/evaluation/evaluator/ThrowEvaluator.kt

@@ -4,16 +4,29 @@ import io.smnp.dsl.ast.model.node.Node
 import io.smnp.dsl.ast.model.node.ThrowNode
 import io.smnp.environment.Environment
 import io.smnp.error.CustomException
+import io.smnp.error.EvaluationException
 import io.smnp.evaluation.model.entity.EvaluatorOutput
+import io.smnp.evaluation.util.ContextExceptionFactory
+import io.smnp.evaluation.util.ContextExceptionFactory.contextEvaluationException
+import io.smnp.evaluation.util.ContextExceptionFactory.wrapWithContext
+import io.smnp.type.enumeration.DataType
 
 class ThrowEvaluator : Evaluator() {
-    override fun supportedNodes() = listOf(ThrowNode::class)
+   override fun supportedNodes() = listOf(ThrowNode::class)
 
-    override fun tryToEvaluate(node: Node, environment: Environment): EvaluatorOutput {
-        val evaluator = ExpressionEvaluator()
-        val valueNode = (node as ThrowNode).value
-        val value = evaluator.evaluate(valueNode, environment)
+   override fun tryToEvaluate(node: Node, environment: Environment): EvaluatorOutput {
+      val evaluator = ExpressionEvaluator()
+      val valueNode = (node as ThrowNode).value
+      val value = evaluator.evaluate(valueNode, environment).value
 
-        throw CustomException(value.value.value.toString())
-    }
+      if (value.type != DataType.STRING) {
+         throw contextEvaluationException(
+            "Only string values can be thrown with 'throw' statement, found ${value.typeName}",
+            valueNode.position,
+            environment
+         )
+      }
+
+      throw wrapWithContext(CustomException(value.value as String), node.position, environment)
+   }
 }