very elegant extension API and parts of it used in std as POC

orchid-std/src/std.rs

@@ -0,0 +1,30 @@
+use orchid_extension::atom::owned_atom_info;
+use orchid_extension::fs::DeclFs;
+use orchid_extension::system::{System, SystemCard};
+use orchid_extension::system_ctor::SystemCtor;
+use orchid_extension::tree::GenTree;
+
+use crate::string::str_atom::StringAtom;
+use crate::string::str_leer::StringLexer;
+
+#[derive(Default)]
+pub struct StdSystem;
+impl SystemCtor for StdSystem {
+  type Deps = ();
+  type Instance = Self;
+  const NAME: &'static str = "orchid::std";
+  const VERSION: f64 = 0.00_01;
+  fn inst() -> Option<Self::Instance> { Some(StdSystem) }
+}
+impl SystemCard for StdSystem {
+  type Ctor = Self;
+  const ATOM_DEFS: &'static [Option<orchid_extension::atom::AtomInfo>] =
+    &[Some(owned_atom_info::<StringAtom>())];
+}
+impl System for StdSystem {
+  fn lexers() -> Vec<orchid_extension::lexer::LexerObj> { vec![&StringLexer] }
+  fn vfs() -> DeclFs { DeclFs::Mod(&[]) }
+  fn env() -> GenTree {
+    GenTree::module([("std", GenTree::module([("string", GenTree::module([]))]))])
+  }
+}