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petitparser/lib/src/lisp/cons.dart

-part of lisp;
-
-/**
- * The basic data structure of LISP.
- */
-class Cons {
-
-  /** The head of the cons. */
-  dynamic head;
-
-  /** The tail of the cons. */
-  dynamic tail;
-
-  /** Constructs a cons. */
-  Cons(this.head, this.tail);
-
-  @override
-  bool operator ==(other) {
-    return other is Cons && head == other.head && tail == other.tail;
-  }
-
-  @override
-  int get hashCode => 31 * head.hashCode + tail.hashCode;
-
-  @override
-  String toString() {
-    var buffer = new StringBuffer();
-    buffer.write('(');
-    var current = this;
-    while (current is Cons) {
-      buffer.write(current.head.toString());
-      current = current.tail;
-      if (current != null) {
-        buffer.write(' ');
-      }
-    }
-    if (current != null) {
-      buffer.write('. ');
-      buffer.write(current);
-    }
-    buffer.write(')');
-    return buffer.toString();
-  }
-}