Add 'Namespace' a container for tags and filters

Stencil/Namespace.swift

@@ -0,0 +1,44 @@
+public class Namespace {
+  public typealias TagParser = (TokenParser, Token) throws -> NodeType
+
+  var tags = [String: TagParser]()
+  var filters = [String: Filter]()
+
+  public init() {
+    registerDefaultTags()
+    registerDefaultFilters()
+  }
+
+  private func registerDefaultTags() {
+    registerTag("for", parser: ForNode.parse)
+    registerTag("if", parser: IfNode.parse)
+    registerTag("ifnot", parser: IfNode.parse_ifnot)
+    registerTag("now", parser: NowNode.parse)
+    registerTag("include", parser: IncludeNode.parse)
+    registerTag("extends", parser: ExtendsNode.parse)
+    registerTag("block", parser: BlockNode.parse)
+  }
+
+  private func registerDefaultFilters() {
+    registerFilter("capitalize", filter: capitalise)
+    registerFilter("uppercase", filter: uppercase)
+    registerFilter("lowercase", filter: lowercase)
+  }
+
+  /// Registers a new template tag
+  public func registerTag(name: String, parser: TagParser) {
+    tags[name] = parser
+  }
+
+  /// Registers a simple template tag with a name and a handler
+  public func registerSimpleTag(name: String, handler: Context throws -> String) {
+    registerTag(name, parser: { parser, token in
+      return SimpleNode(handler: handler)
+    })
+  }
+
+  /// Registers a template filter with the given name
+  public func registerFilter(name: String, filter: Filter) {
+    filters[name] = filter
+  }
+}

Stencil/Parser.swift

@@ -16,38 +16,12 @@ public typealias Filter = Any? throws -> Any?
 public class TokenParser {
   public typealias TagParser = (TokenParser, Token) throws -> NodeType
 
-  private var tokens:[Token]
-  private var tags = [String:TagParser]()
-  private var filters = [String: Filter]()
+  private var tokens: [Token]
+  private let namespace: Namespace
 
-  public init(tokens:[Token]) {
+  public init(tokens: [Token], namespace: Namespace) {
     self.tokens = tokens
-    registerTag("for", parser: ForNode.parse)
-    registerTag("if", parser: IfNode.parse)
-    registerTag("ifnot", parser: IfNode.parse_ifnot)
-    registerTag("now", parser: NowNode.parse)
-    registerTag("include", parser: IncludeNode.parse)
-    registerTag("extends", parser: ExtendsNode.parse)
-    registerTag("block", parser: BlockNode.parse)
-    registerFilter("capitalize", filter: capitalise)
-    registerFilter("uppercase", filter: uppercase)
-    registerFilter("lowercase", filter: lowercase)
-  }
-
-  /// Registers a new template tag
-  public func registerTag(name:String, parser:TagParser) {
-    tags[name] = parser
-  }
-
-  /// Registers a simple template tag with a name and a handler
-  public func registerSimpleTag(name:String, handler:(Context throws -> String)) {
-    registerTag(name, parser: { parser, token in
-      return SimpleNode(handler: handler)
-    })
-  }
-
-  public func registerFilter(name: String, filter: Filter) {
-    filters[name] = filter
+    self.namespace = namespace
   }
 
   /// Parse the given tokens into nodes
@@ -75,7 +49,7 @@ public class TokenParser {
         }
 
         if let tag = tag {
-          if let parser = self.tags[tag] {
+          if let parser = namespace.tags[tag] {
             nodes.append(try parser(self, token))
           } else {
             throw TemplateSyntaxError("Unknown template tag '\(tag)'")
@@ -102,7 +76,7 @@ public class TokenParser {
   }
 
   public func findFilter(name: String) throws -> Filter {
-    if let filter = filters[name] {
+    if let filter = namespace.filters[name] {
       return filter
     }
 

Stencil/Template.swift

@@ -3,8 +3,7 @@ import PathKit
 
 /// A class representing a template
 public class Template {
-  public let parser:TokenParser
-  private var nodes:[NodeType]? = nil
+  let tokens: [Token]
 
   /// Create a template with the given name inside the given bundle
   public convenience init(named:String, inBundle bundle:NSBundle? = nil) throws {
@@ -29,16 +28,13 @@ public class Template {
   /// Create a template with a template string
   public init(templateString:String) {
     let lexer = Lexer(templateString: templateString)
-    let tokens = lexer.tokenize()
-    parser = TokenParser(tokens: tokens)
+    tokens = lexer.tokenize()
   }
 
   /// Render the given template
-  public func render(context:Context? = nil) throws -> String {
-    if nodes == nil {
-        nodes = try parser.parse()
-    }
-
-    return try renderNodes(nodes!, context ?? Context())
+  public func render(context: Context? = nil, namespace: Namespace? = nil) throws -> String {
+    let parser = TokenParser(tokens: tokens, namespace: namespace ?? Namespace())
+    let nodes = try parser.parse()
+    return try renderNodes(nodes, context ?? Context())
   }
 }