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- package Ast;
- use strict;
-
- use vars qw/ $this $pack @endCodes /;
-
- #-----------------------------------------------------------------------------
- # This package is used to create a simple Abstract Syntax tree. Each node
- # in the AST is an associative array and supports two kinds of properties -
- # scalars and lists of scalars.
- # See SchemParser.pm for an example of usage.
- # ... Sriram
- #-----------------------------------------------------------------------------
-
- # Constructor
- # e.g AST::New ("personnel")
- # Stores the argument in a property called astNodeName whose sole purpose
- # is to support Print()
-
- sub New {
- my ($this) = {"astNodeName" => $_[0]};
- bless ($this);
- return $this;
- }
-
- # Add a property to this object
- # $astNode->AddProp("className", "Employee");
-
- sub AddProp {
- my ($this) = $_[0];
- $this->{$_[1]} = $_[2];
- }
-
- # Equivalent to AddProp, except the property name is associated
- # with a list of values
- # $classAstNode->AddProp("attrList", $attrAstNode);
-
- sub AddPropList {
- my ($this) = $_[0];
- if (! exists $this->{$_[1]}) {
- $this->{$_[1]} = [];
- }
- push (@{$this->{$_[1]}}, $_[2]);
- }
-
- # Returns a list of all the property names of this object
- sub GetProps {
- my ($this) = $_[0];
- return keys %{$this};
- }
-
- 1;
-