module parser_nodes
import location
+import ordered_tree
# Root of the AST class-hierarchy
abstract class ANode
sys.stderr.write "{hot_location} {self.class_name}: {message}\n{hot_location.colored_line("0;32")}\n"
end
+ # Write the subtree on stdout.
+ # See `ASTDump`
+ fun dump_tree
+ do
+ var d = new ASTDump
+ d.enter_visit(self)
+ d.write_to(sys.stdout)
+ end
+
# Parent of the node in the AST
var parent: nullable ANode = null
end
end
+# A helper class to handle (print) Nit AST as an OrderedTree
+class ASTDump
+ super Visitor
+ super OrderedTree[ANode]
+
+ # Reference to the last parent in the Ordered Tree
+ # Is used to handle the initial node parent and workaround possible inconsistent `ANode::parent`
+ private var last_parent: nullable ANode = null
+
+ redef fun visit(n)
+ do
+ var p = last_parent
+ add(p, n)
+ last_parent = n
+ n.visit_all(self)
+ last_parent = p
+ end
+
+ redef fun display(n)
+ do
+ if n isa Token then
+ return "{n.class_name} \"{n.text.escape_to_c}\" @{n.location}"
+ else
+ return "{n.class_name} @{n.location}"
+ end
+ end
+end
# A sequence of nodes
# It is a specific class (instead of using a Array) to track the parent/child relation when nodes are added or removed