refactor: Introducing Environments

Sources/Environment.swift

@@ -0,0 +1,36 @@
+public struct Environment {
+  var namespace: Namespace
+
+  public var loader: Loader?
+
+  public init(loader: Loader? = nil, namespace: Namespace? = nil) {
+    self.loader = loader
+    self.namespace = namespace ?? Namespace()
+  }
+
+  public func loadTemplate(name: String) throws -> Template {
+    if let loader = loader {
+      return try loader.loadTemplate(name: name, environment: self)
+    } else {
+      throw TemplateDoesNotExist(templateNames: [name], loader: nil)
+    }
+  }
+
+  public func loadTemplate(names: [String]) throws -> Template {
+    if let loader = loader {
+      return try loader.loadTemplate(names: names, environment: self)
+    } else {
+      throw TemplateDoesNotExist(templateNames: names, loader: nil)
+    }
+  }
+
+  public func renderTemplate(name: String, context: [String: Any]? = nil) throws -> String {
+    let template = try loadTemplate(name: name)
+    return try template.render(context)
+  }
+
+  public func renderTemplate(string: String, context: [String: Any]? = nil) throws -> String {
+    let template = Template(templateString: string, environment: self)
+    return try template.render(context)
+  }
+}