Change: overhaul Statement

Redefines Statement from an enum containing all information to a struct.

This Statement struct contains a start and end token as well as a
`StatementKind`. The kind contains all necessary information for
execution.

The Statement also contains information about start and end to make it
also useful when working with code manipulation e.g. transpiling.

This refactoring allows us to extend Statement information, for e.g. a
formatter, while not having to change the interpreter itself.

Overall this should give us more freedom to extend Statements.

rust/feed/src/oid/mod.rs

@@ -7,7 +7,7 @@
 use std::{fs::File, io::Read};
 
 use nasl_interpreter::{AsBufReader, Loader};
-use nasl_syntax::{IdentifierType, Statement, TokenCategory};
+use nasl_syntax::{IdentifierType, Statement, StatementKind, TokenCategory};
 
 use crate::{
     update,
@@ -40,10 +40,11 @@ where
     }
 
     fn script_oid(stmt: &Statement) -> Option<String> {
-        match stmt {
-            Statement::Call(t, stms, _) => match t.category() {
+        match stmt.kind() {
+            StatementKind::Call(param) => match stmt.start().category() {
                 TokenCategory::Identifier(IdentifierType::Undefined(s)) => match s as &str {
-                    "script_oid" => stms.first().map(|x| x.to_string()),
+                    // maybe switch from children to patternmatching?
+                    "script_oid" => param.children().first().map(|x| x.to_string()),
                     _ => None,
                 },
                 _ => None,
@@ -56,8 +57,8 @@ where
     fn single(&self, key: String) -> Result<String, update::ErrorKind> {
         let code = self.loader.load(key.as_ref())?;
         for stmt in nasl_syntax::parse(&code) {
-            if let Statement::If(_, _, stmts, _, _) = stmt? {
-                if let Statement::Block(_, x, _) = &*stmts {
+            if let StatementKind::If(_, stmts, _, _) = stmt?.kind() {
+                if let StatementKind::Block(x) = stmts.kind() {
                     for stmt in x {
                         if let Some(oid) = Self::script_oid(stmt) {
                             return Ok(oid);