env module stub

src/interpreter/program.rs

@@ -4,7 +4,8 @@ use std::collections::hash_map::Entry;
 use parking_lot::RwLock;
 use elements::Module;
 use interpreter::Error;
-use interpreter::module::ModuleInstance;
+use interpreter::env::env_module;
+use interpreter::module::{ModuleInstance, ModuleInstanceInterface};
 
 /// Program instance. Program is a set of instantiated modules.
 pub struct ProgramInstance {
@@ -15,15 +16,15 @@ pub struct ProgramInstance {
 /// Program instance essence.
 pub struct ProgramInstanceEssence {
 	/// Loaded modules.
-	modules: RwLock<HashMap<String, Arc<ModuleInstance>>>,
+	modules: RwLock<HashMap<String, Arc<ModuleInstanceInterface>>>,
 }
 
 impl ProgramInstance {
 	/// Create new program instance.
-	pub fn new() -> Self {
-		ProgramInstance {
-			essence: Arc::new(ProgramInstanceEssence::new()),
-		}
+	pub fn new() -> Result<Self, Error> {
+		Ok(ProgramInstance {
+			essence: Arc::new(ProgramInstanceEssence::new()?),
+		})
 	}
 
 	/// Instantiate module.
@@ -42,14 +43,17 @@ impl ProgramInstance {
 
 impl ProgramInstanceEssence {
 	/// Create new program essence.
-	pub fn new() -> Self {
-		ProgramInstanceEssence {
-			modules: RwLock::new(HashMap::new()),
-		}
+	pub fn new() -> Result<Self, Error> {
+		let mut modules = HashMap::new();
+		let env_module: Arc<ModuleInstanceInterface> = Arc::new(env_module()?);
+		modules.insert("env".into(), env_module);
+		Ok(ProgramInstanceEssence {
+			modules: RwLock::new(modules),
+		})
 	}
 
 	/// Get module reference.
-	pub fn module(&self, name: &str) -> Option<Arc<ModuleInstance>> {
+	pub fn module(&self, name: &str) -> Option<Arc<ModuleInstanceInterface>> {
 		self.modules.read().get(name).cloned()
 	}
 }