Class RewriteRuleSubtreeStream

java.lang.Object
org.antlr.runtime.tree.RewriteRuleElementStream
org.antlr.runtime.tree.RewriteRuleSubtreeStream

public class RewriteRuleSubtreeStream extends RewriteRuleElementStream
  • Constructor Details

    • RewriteRuleSubtreeStream

      public RewriteRuleSubtreeStream(TreeAdaptor adaptor, String elementDescription)
    • RewriteRuleSubtreeStream

      public RewriteRuleSubtreeStream(TreeAdaptor adaptor, String elementDescription, Object oneElement)
      Create a stream with one element
    • RewriteRuleSubtreeStream

      public RewriteRuleSubtreeStream(TreeAdaptor adaptor, String elementDescription, List elements)
      Create a stream, but feed off an existing list
  • Method Details

    • nextNode

      public Object nextNode()
      Treat next element as a single node even if it's a subtree. This is used instead of next() when the result has to be a tree root node. Also prevents us from duplicating recently-added children; e.g., ^(type ID)+ adds ID to type and then 2nd iteration must dup the type node, but ID has been added. Referencing a rule result twice is ok; dup entire tree as we can't be adding trees as root; e.g., expr expr. Hideous code duplication here with super.next(). Can't think of a proper way to refactor. This needs to always call dup node and super.next() doesn't know which to call: dup node or dup tree.
    • dup

      protected Object dup(Object el)
      Description copied from class: RewriteRuleElementStream
      When constructing trees, sometimes we need to dup a token or AST subtree. Dup'ing a token means just creating another AST node around it. For trees, you must call the adaptor.dupTree() unless the element is for a tree root; then it must be a node dup.
      Specified by:
      dup in class RewriteRuleElementStream