There have been multiple implementations of infix-notation Lisps and Lisp-like or Lisp-derived languages. This can mean stuttering, lisps, etc. Special letters are included to transcribe the speech of people with lisps and cleft palates. Other calls include lisps, peeps, and more rapidly whistled warning calls. Early Lisps had many limitations, including limited data types and slow numerics. These earlier Lisps implemented lexical scoping in the compiler and dynamic scoping in the interpreter. Similar to other Lisps, Clojure is homoiconic (also known as code as data). All early Lisps used dynamic scoping, at least when based on interpreters. In the episode "iStart a Fan War," it is shown that Stacey lisps again. Most Lisps specify an order of evaluation for procedure arguments. Some Lisps provide "funcallable" objects as a simple extension. The Lisps is a New York-based indie rock band. So Lisps are useful for learning language design, and creating custom languages.