EuLisp

Distinguishing features

Its main traits are that it is a Lisp-1 (no separate function and variable namespaces), has a Common Lisp Object System (CLOS) style generic-function type object-oriented system named The EuLisp Object System (TELOS) integrated from the ground up, has a built-in module system, and is defined in layers to promote the use of the Lisp on small, embedded hardware and educational machines. It supports continuations, though not as powerfully as Scheme. It has a simple lightweight process mechanism (threads).

Summary

• A definition in levels, currently Level-0 and Level-1
• Modules based on (non-first-class) lexical environments.
• Lexically scoped, with dynamic or late binding available in Level-1.
• A single name space for function and variable names (like Scheme).
• Lightweight processes.
• A fully integrated object system with single inheritance at Level-0 and multiple inheritance and meta-object protocol at Level-1.
• An object-oriented condition system.

Implementations

An early implementation of EuLisp was Free and Eventually Eulisp (FEEL). The successor to FEEL was Youtoo (interpreted and compiled versions), by University of Bath in the United Kingdom. An interpreter for the basic level of EuLisp, level-0, was written by Russell Bradford in XScheme, an implementation of Scheme by David Michael Betz, originally named EuScheme EuScheme but the most recent version is renamed EuXLisp to avoid confusion. Also Eu2C , a EuLisp optimizing compiler, was created by Fraunhofer ISST under the APPLY project in Germany .

A dialect of EuLisp was developed, named Plural EuLisp. It was EuLisp with parallel computing programming extensions.

Example

Example use of classes in the algorithm to solve the "Towers of Hanoi" problem.

<span id="mwUQ"></span><span class="p" id="mwUg">(</span><span class="nv" id="mwUw">defmodule</span><span class="w" id="mwVA"> </span><span class="nv" id="mwVQ">hanoi</span> <span class="w" id="mwVg"> </span><span class="p" id="mwVw">(</span><span class="nv" id="mwWA">syntax</span><span class="w" id="mwWQ"> </span><span class="p" id="mwWg">(</span><span class="nv" id="mwWw">syntax-0</span><span class="p" id="mwXA">)</span> <span class="w" id="mwXQ"> </span><span class="nb" id="mwXg">import</span><span class="w" id="mwXw"> </span><span class="p" id="mwYA">(</span><span class="nv" id="mwYQ">level-0</span><span class="p" id="mwYg">)</span> <span class="w" id="mwYw"> </span><span class="nb" id="mwZA">export</span><span class="w" id="mwZQ"> </span><span class="p" id="mwZg">(</span><span class="nv" id="mwZw">hanoi</span><span class="p" id="mwaA">))</span> <span class="c1" id="mwaQ">;;;-------------------------------------------------</span> <span class="c1" id="mwag">;;; Tower definition</span> <span class="c1" id="mwaw">;;;-------------------------------------------------</span> <span class="p" id="mwbA">(</span><span class="nb" id="mwbQ">defconstant</span><span class="w" id="mwbg"> </span><span class="vg" id="mwbw">*max-tower-height*</span><span class="w" id="mwcA"> </span><span class="mi" id="mwcQ">10</span><span class="p" id="mwcg">)</span> <span class="p" id="mwcw">(</span><span class="nb" id="mwdA">defclass</span><span class="w" id="mwdQ"> </span><span class="nv" id="mwdg"><tower></span><span class="w" id="mwdw"> </span><span class="p" id="mweA">()</span> <span class="w" id="mweQ"> </span><span class="p" id="mweg">((</span><span class="nv" id="mwew">id</span><span class="w" id="mwfA"> </span><span class="nv" id="mwfQ">reader:</span><span class="w" id="mwfg"> </span><span class="nv" id="mwfw">tower-id</span><span class="w" id="mwgA"> </span><span class="nv" id="mwgQ">keyword:</span><span class="w" id="mwgg"> </span><span class="nv" id="mwgw">id:</span><span class="p" id="mwhA">)</span> <span class="w" id="mwhQ"> </span><span class="p" id="mwhg">(</span><span class="nv" id="mwhw">blocks</span><span class="w" id="mwiA"> </span><span class="nv" id="mwiQ">accessor:</span><span class="w" id="mwig"> </span><span class="nv" id="mwiw">tower-blocks</span><span class="p" id="mwjA">)))</span> <span class="p" id="mwjQ">(</span><span class="nb" id="mwjg">defun</span><span class="w" id="mwjw"> </span><span class="nv" id="mwkA">build-tower</span><span class="w" id="mwkQ"> </span><span class="p" id="mwkg">(</span><span class="nv" id="mwkw">x</span><span class="w" id="mwlA"> </span><span class="nv" id="mwlQ">n</span><span class="p" id="mwlg">)</span> <span class="w" id="mwlw"> </span><span class="p" id="mwmA">(</span><span class="k" id="mwmQ">labels</span><span class="w" id="mwmg"> </span><span class="p" id="mwmw">((</span><span class="nb" id="mwnA">loop</span><span class="w" id="mwnQ"> </span><span class="p" id="mwng">(</span><span class="nv" id="mwnw">i</span><span class="w" id="mwoA"> </span><span class="nv" id="mwoQ">res</span><span class="p" id="mwog">)</span> <span class="w" id="mwow"> </span><span class="p" id="mwpA">(</span><span class="k" id="mwpQ">if</span><span class="w" id="mwpg"> </span><span class="p" id="mwpw">(</span><span class="nb" id="mwqA">=</span><span class="w" id="mwqQ"> </span><span class="nv" id="mwqg">i</span><span class="w" id="mwqw"> </span><span class="mi" id="mwrA">0</span><span class="p" id="mwrQ">)</span><span class="w" id="mwrg"> </span><span class="nv" id="mwrw">res</span> <span class="w" id="mwsA"> </span><span class="p" id="mwsQ">(</span><span class="nb" id="mwsg">loop</span><span class="w" id="mwsw"> </span><span class="p" id="mwtA">(</span><span class="nb" id="mwtQ">-</span><span class="w" id="mwtg"> </span><span class="nv" id="mwtw">i</span><span class="w" id="mwuA"> </span><span class="mi" id="mwuQ">1</span><span class="p" id="mwug">)</span><span class="w" id="mwuw"> </span><span class="p" id="mwvA">(</span><span class="nb" id="mwvQ">cons</span><span class="w" id="mwvg"> </span><span class="nv" id="mwvw">i</span><span class="w" id="mwwA"> </span><span class="nv" id="mwwQ">res</span><span class="p" id="mwwg">)))))</span> <span class="w" id="mwww"> </span><span class="p" id="mwxA">((</span><span class="nv" id="mwxQ">setter</span><span class="w" id="mwxg"> </span><span class="nv" id="mwxw">tower-blocks</span><span class="p" id="mwyA">)</span><span class="w" id="mwyQ"> </span><span class="nv" id="mwyg">x</span><span class="w" id="mwyw"> </span><span class="p" id="mwzA">(</span><span class="nb" id="mwzQ">loop</span><span class="w" id="mwzg"> </span><span class="nv" id="mwzw">n</span><span class="w" id="mw0A"> </span><span class="p" id="mw0Q">()))</span> <span class="w" id="mw0g"> </span><span class="nv" id="mw0w">x</span><span class="p" id="mw1A">))</span> <span class="p" id="mw1Q">(</span><span class="nb" id="mw1g">defmethod</span><span class="w" id="mw1w"> </span><span class="nv" id="mw2A">generic-print</span><span class="w" id="mw2Q"> </span><span class="p" id="mw2g">((</span><span class="nv" id="mw2w">x</span><span class="w" id="mw3A"> </span><span class="nv" id="mw3Q"><tower></span><span class="p" id="mw3g">)</span><span class="w" id="mw3w"> </span><span class="p" id="mw4A">(</span><span class="nv" id="mw4Q">s</span><span class="w" id="mw4g"> </span><span class="nv" id="mw4w"><stream></span><span class="p" id="mw5A">))</span> <span class="w" id="mw5Q"> </span><span class="p" id="mw5g">(</span><span class="nv" id="mw5w">sformat</span><span class="w" id="mw6A"> </span><span class="nv" id="mw6Q">s</span><span class="w" id="mw6g"> </span><span class="s" id="mw6w">"#<tower ~a: ~a>"</span><span class="w" id="mw7A"> </span><span class="p" id="mw7Q">(</span><span class="nv" id="mw7g">tower-id</span><span class="w" id="mw7w"> </span><span class="nv" id="mw8A">x</span><span class="p" id="mw8Q">)</span><span class="w" id="mw8g"> </span><span class="p" id="mw8w">(</span><span class="nv" id="mw9A">tower-blocks</span><span class="w" id="mw9Q"> </span><span class="nv" id="mw9g">x</span><span class="p" id="mw9w">)))</span> <span class="c1" id="mw-A">;;;-------------------------------------------------</span> <span class="c1" id="mw-Q">;;; Access to tower blocks</span> <span class="c1" id="mw-g">;;;-------------------------------------------------</span> <span class="p" id="mw-w">(</span><span class="nb" id="mw_A">defgeneric</span><span class="w" id="mw_Q"> </span><span class="nb" id="mw_g">push</span><span class="w" id="mw_w"> </span><span class="p" id="mwAQA">(</span><span class="nv" id="mwAQE">x</span><span class="w" id="mwAQI"> </span><span class="nv" id="mwAQM">y</span><span class="p" id="mwAQQ">))</span> <span class="p" id="mwAQU">(</span><span class="nb" id="mwAQY">defmethod</span><span class="w" id="mwAQc"> </span><span class="nb" id="mwAQg">push</span><span class="w" id="mwAQk"> </span><span class="p" id="mwAQo">((</span><span class="nv" id="mwAQs">x</span><span class="w" id="mwAQw"> </span><span class="nv" id="mwAQ0"><tower></span><span class="p" id="mwAQ4">)</span><span class="w" id="mwAQ8"> </span><span class="p" id="mwARA">(</span><span class="nv" id="mwARE">y</span><span class="w" id="mwARI"> </span><span class="nv" id="mwARM"><fpi></span><span class="p" id="mwARQ">))</span> <span class="w" id="mwARU"> </span><span class="p" id="mwARY">(</span><span class="k" id="mwARc">let</span><span class="w" id="mwARg"> </span><span class="p" id="mwARk">((</span><span class="nv" id="mwARo">blocks</span><span class="w" id="mwARs"> </span><span class="p" id="mwARw">(</span><span class="nv" id="mwAR0">tower-blocks</span><span class="w" id="mwAR4"> </span><span class="nv" id="mwAR8">x</span><span class="p" id="mwASA">)))</span> <span class="w" id="mwASE"> </span><span class="p" id="mwASI">(</span><span class="k" id="mwASM">if</span><span class="w" id="mwASQ"> </span><span class="p" id="mwASU">(</span><span class="nb" id="mwASY">or</span><span class="w" id="mwASc"> </span><span class="p" id="mwASg">(</span><span class="nv" id="mwASk">null?</span><span class="w" id="mwASo"> </span><span class="nv" id="mwASs">blocks</span><span class="p" id="mwASw">)</span><span class="w" id="mwAS0"> </span><span class="p" id="mwAS4">(</span><span class="nb" id="mwAS8"><</span><span class="w" id="mwATA"> </span><span class="nv" id="mwATE">y</span><span class="w" id="mwATI"> </span><span class="p" id="mwATM">(</span><span class="nb" id="mwATQ">car</span><span class="w" id="mwATU"> </span><span class="nv" id="mwATY">blocks</span><span class="p" id="mwATc">)))</span> <span class="w" id="mwATg"> </span><span class="p" id="mwATk">((</span><span class="nv" id="mwATo">setter</span><span class="w" id="mwATs"> </span><span class="nv" id="mwATw">tower-blocks</span><span class="p" id="mwAT0">)</span><span class="w" id="mwAT4"> </span><span class="nv" id="mwAT8">x</span><span class="w" id="mwAUA"> </span><span class="p" id="mwAUE">(</span><span class="nb" id="mwAUI">cons</span><span class="w" id="mwAUM"> </span><span class="nv" id="mwAUQ">y</span><span class="w" id="mwAUU"> </span><span class="nv" id="mwAUY">blocks</span><span class="p" id="mwAUc">))</span> <span class="w" id="mwAUg"> </span><span class="p" id="mwAUk">(</span><span class="nb" id="mwAUo">error</span><span class="w" id="mwAUs"> </span><span class="nv" id="mwAUw"><condition></span> <span class="w" id="mwAU0"> </span><span class="p" id="mwAU4">(</span><span class="nv" id="mwAU8">fmt</span><span class="w" id="mwAVA"> </span><span class="s" id="mwAVE">"cannot push block of size ~a on tower ~a"</span><span class="w" id="mwAVI"> </span><span class="nv" id="mwAVM">y</span><span class="w" id="mwAVQ"> </span><span class="nv" id="mwAVU">x</span><span class="p" id="mwAVY">)))))</span> <span class="p" id="mwAVc">(</span><span class="nb" id="mwAVg">defgeneric</span><span class="w" id="mwAVk"> </span><span class="nb" id="mwAVo">pop</span><span class="w" id="mwAVs"> </span><span class="p" id="mwAVw">(</span><span class="nv" id="mwAV0">x</span><span class="p" id="mwAV4">))</span> <span class="p" id="mwAV8">(</span><span class="nb" id="mwAWA">defmethod</span><span class="w" id="mwAWE"> </span><span class="nb" id="mwAWI">pop</span><span class="w" id="mwAWM"> </span><span class="p" id="mwAWQ">((</span><span class="nv" id="mwAWU">x</span><span class="w" id="mwAWY"> </span><span class="nv" id="mwAWc"><tower></span><span class="p" id="mwAWg">))</span> <span class="w" id="mwAWk"> </span><span class="p" id="mwAWo">(</span><span class="k" id="mwAWs">let</span><span class="w" id="mwAWw"> </span><span class="p" id="mwAW0">((</span><span class="nv" id="mwAW4">blocks</span><span class="w" id="mwAW8"> </span><span class="p" id="mwAXA">(</span><span class="nv" id="mwAXE">tower-blocks</span><span class="w" id="mwAXI"> </span><span class="nv" id="mwAXM">x</span><span class="p" id="mwAXQ">)))</span> <span class="w" id="mwAXU"> </span><span class="p" id="mwAXY">(</span><span class="k" id="mwAXc">if</span><span class="w" id="mwAXg"> </span><span class="nv" id="mwAXk">blocks</span> <span class="w" id="mwAXo"> </span><span class="p" id="mwAXs">(</span><span class="k" id="mwAXw">progn</span> <span class="w" id="mwAX0"> </span><span class="p" id="mwAX4">((</span><span class="nv" id="mwAX8">setter</span><span class="w" id="mwAYA"> </span><span class="nv" id="mwAYE">tower-blocks</span><span class="p" id="mwAYI">)</span><span class="w" id="mwAYM"> </span><span class="nv" id="mwAYQ">x</span><span class="w" id="mwAYU"> </span><span class="p" id="mwAYY">(</span><span class="nb" id="mwAYc">cdr</span><span class="w" id="mwAYg"> </span><span class="nv" id="mwAYk">blocks</span><span class="p" id="mwAYo">))</span> <span class="w" id="mwAYs"> </span><span class="p" id="mwAYw">(</span><span class="nb" id="mwAY0">car</span><span class="w" id="mwAY4"> </span><span class="nv" id="mwAY8">blocks</span><span class="p" id="mwAZA">))</span> <span class="w" id="mwAZE"> </span><span class="p" id="mwAZI">(</span><span class="nb" id="mwAZM">error</span><span class="w" id="mwAZQ"> </span><span class="nv" id="mwAZU"><condition></span> <span class="w" id="mwAZY"> </span><span class="p" id="mwAZc">(</span><span class="nv" id="mwAZg">fmt</span><span class="w" id="mwAZk"> </span><span class="s" id="mwAZo">"cannot pop block from empty tower ~a"</span><span class="w" id="mwAZs"> </span><span class="nv" id="mwAZw">x</span><span class="p" id="mwAZ0">)))))</span> <span class="c1" id="mwAZ4">;;;-------------------------------------------------</span> <span class="c1" id="mwAZ8">;;; Move n blocks from tower x1 to tower x2 using x3 as buffer</span> <span class="c1" id="mwAaA">;;;-------------------------------------------------</span> <span class="p" id="mwAaE">(</span><span class="nb" id="mwAaI">defgeneric</span><span class="w" id="mwAaM"> </span><span class="nv" id="mwAaQ">move</span><span class="w" id="mwAaU"> </span><span class="p" id="mwAaY">(</span><span class="nv" id="mwAac">n</span><span class="w" id="mwAag"> </span><span class="nv" id="mwAak">x1</span><span class="w" id="mwAao"> </span><span class="nv" id="mwAas">x2</span><span class="w" id="mwAaw"> </span><span class="nv" id="mwAa0">x3</span><span class="p" id="mwAa4">))</span> <span class="p" id="mwAa8">(</span><span class="nb" id="mwAbA">defmethod</span><span class="w" id="mwAbE"> </span><span class="nv" id="mwAbI">move</span><span class="w" id="mwAbM"> </span><span class="p" id="mwAbQ">((</span><span class="nv" id="mwAbU">n</span><span class="w" id="mwAbY"> </span><span class="nv" id="mwAbc"><fpi></span><span class="p" id="mwAbg">)</span><span class="w" id="mwAbk"> </span><span class="p" id="mwAbo">(</span><span class="nv" id="mwAbs">x1</span><span class="w" id="mwAbw"> </span><span class="nv" id="mwAb0"><tower></span><span class="p" id="mwAb4">)</span><span class="w" id="mwAb8"> </span><span class="p" id="mwAcA">(</span><span class="nv" id="mwAcE">x2</span><span class="w" id="mwAcI"> </span><span class="nv" id="mwAcM"><tower></span><span class="p" id="mwAcQ">)</span><span class="w" id="mwAcU"> </span><span class="p" id="mwAcY">(</span><span class="nv" id="mwAcc">x3</span><span class="w" id="mwAcg"> </span><span class="nv" id="mwAck"><tower></span><span class="p" id="mwAco">))</span> <span class="w" id="mwAcs"> </span><span class="p" id="mwAcw">(</span><span class="k" id="mwAc0">if</span><span class="w" id="mwAc4"> </span><span class="p" id="mwAc8">(</span><span class="nb" id="mwAdA">=</span><span class="w" id="mwAdE"> </span><span class="nv" id="mwAdI">n</span><span class="w" id="mwAdM"> </span><span class="mi" id="mwAdQ">1</span><span class="p" id="mwAdU">)</span> <span class="w" id="mwAdY"> </span><span class="p" id="mwAdc">(</span><span class="k" id="mwAdg">progn</span> <span class="w" id="mwAdk"> </span><span class="p" id="mwAdo">(</span><span class="nb" id="mwAds">push</span><span class="w" id="mwAdw"> </span><span class="nv" id="mwAd0">x2</span><span class="w" id="mwAd4"> </span><span class="p" id="mwAd8">(</span><span class="nb" id="mwAeA">pop</span><span class="w" id="mwAeE"> </span><span class="nv" id="mwAeI">x1</span><span class="p" id="mwAeM">))</span> <span class="w" id="mwAeQ"> </span><span class="p" id="mwAeU">(</span><span class="nb" id="mwAeY">print</span><span class="w" id="mwAec"> </span><span class="nv" id="mwAeg">x1</span><span class="w" id="mwAek"> </span><span class="nv" id="mwAeo">nl</span><span class="w" id="mwAes"> </span><span class="nv" id="mwAew">x2</span><span class="w" id="mwAe0"> </span><span class="nv" id="mwAe4">nl</span><span class="w" id="mwAe8"> </span><span class="nv" id="mwAfA">x3</span><span class="w" id="mwAfE"> </span><span class="nv" id="mwAfI">nl</span><span class="w" id="mwAfM"> </span><span class="nv" id="mwAfQ">nl</span><span class="p" id="mwAfU">))</span> <span class="w" id="mwAfY"> </span><span class="p" id="mwAfc">(</span><span class="k" id="mwAfg">progn</span> <span class="w" id="mwAfk"> </span><span class="p" id="mwAfo">(</span><span class="nv" id="mwAfs">move</span><span class="w" id="mwAfw"> </span><span class="p" id="mwAf0">(</span><span class="nb" id="mwAf4">-</span><span class="w" id="mwAf8"> </span><span class="nv" id="mwAgA">n</span><span class="w" id="mwAgE"> </span><span class="mi" id="mwAgI">1</span><span class="p" id="mwAgM">)</span><span class="w" id="mwAgQ"> </span><span class="nv" id="mwAgU">x1</span><span class="w" id="mwAgY"> </span><span class="nv" id="mwAgc">x3</span><span class="w" id="mwAgg"> </span><span class="nv" id="mwAgk">x2</span><span class="p" id="mwAgo">)</span> <span class="w" id="mwAgs"> </span><span class="p" id="mwAgw">(</span><span class="nv" id="mwAg0">move</span><span class="w" id="mwAg4"> </span><span class="mi" id="mwAg8">1</span><span class="w" id="mwAhA"> </span><span class="nv" id="mwAhE">x1</span><span class="w" id="mwAhI"> </span><span class="nv" id="mwAhM">x2</span><span class="w" id="mwAhQ"> </span><span class="nv" id="mwAhU">x3</span><span class="p" id="mwAhY">)</span> <span class="w" id="mwAhc"> </span><span class="p" id="mwAhg">(</span><span class="nv" id="mwAhk">move</span><span class="w" id="mwAho"> </span><span class="p" id="mwAhs">(</span><span class="nb" id="mwAhw">-</span><span class="w" id="mwAh0"> </span><span class="nv" id="mwAh4">n</span><span class="w" id="mwAh8"> </span><span class="mi" id="mwAiA">1</span><span class="p" id="mwAiE">)</span><span class="w" id="mwAiI"> </span><span class="nv" id="mwAiM">x3</span><span class="w" id="mwAiQ"> </span><span class="nv" id="mwAiU">x2</span><span class="w" id="mwAiY"> </span><span class="nv" id="mwAic">x1</span><span class="p" id="mwAig">))))</span> <span class="c1" id="mwAik">;;;-------------------------------------------------</span> <span class="c1" id="mwAio">;;; Initialize and run the 'Towers of Hanoi'</span> <span class="c1" id="mwAis">;;;-------------------------------------------------</span> <span class="p" id="mwAiw">(</span><span class="nb" id="mwAi0">defun</span><span class="w" id="mwAi4"> </span><span class="nv" id="mwAi8">hanoi</span><span class="w" id="mwAjA"> </span><span class="p" id="mwAjE">()</span> <span class="w" id="mwAjI"> </span><span class="p" id="mwAjM">(</span><span class="k" id="mwAjQ">let</span><span class="w" id="mwAjU"> </span><span class="p" id="mwAjY">((</span><span class="nv" id="mwAjc">x1</span><span class="w" id="mwAjg"> </span><span class="p" id="mwAjk">(</span><span class="nv" id="mwAjo">make</span><span class="w" id="mwAjs"> </span><span class="nv" id="mwAjw"><tower></span><span class="w" id="mwAj0"> </span><span class="nv" id="mwAj4">id:</span><span class="w" id="mwAj8"> </span><span class="mi" id="mwAkA">0</span><span class="p" id="mwAkE">))</span> <span class="w" id="mwAkI"> </span><span class="p" id="mwAkM">(</span><span class="nv" id="mwAkQ">x2</span><span class="w" id="mwAkU"> </span><span class="p" id="mwAkY">(</span><span class="nv" id="mwAkc">make</span><span class="w" id="mwAkg"> </span><span class="nv" id="mwAkk"><tower></span><span class="w" id="mwAko"> </span><span class="nv" id="mwAks">id:</span><span class="w" id="mwAkw"> </span><span class="mi" id="mwAk0">1</span><span class="p" id="mwAk4">))</span> <span class="w" id="mwAk8"> </span><span class="p" id="mwAlA">(</span><span class="nv" id="mwAlE">x3</span><span class="w" id="mwAlI"> </span><span class="p" id="mwAlM">(</span><span class="nv" id="mwAlQ">make</span><span class="w" id="mwAlU"> </span><span class="nv" id="mwAlY"><tower></span><span class="w" id="mwAlc"> </span><span class="nv" id="mwAlg">id:</span><span class="w" id="mwAlk"> </span><span class="mi" id="mwAlo">2</span><span class="p" id="mwAls">)))</span> <span class="w" id="mwAlw"> </span><span class="p" id="mwAl0">(</span><span class="nv" id="mwAl4">build-tower</span><span class="w" id="mwAl8"> </span><span class="nv" id="mwAmA">x1</span><span class="w" id="mwAmE"> </span><span class="vg" id="mwAmI">*max-tower-height*</span><span class="p" id="mwAmM">)</span> <span class="w" id="mwAmQ"> </span><span class="p" id="mwAmU">(</span><span class="nv" id="mwAmY">build-tower</span><span class="w" id="mwAmc"> </span><span class="nv" id="mwAmg">x2</span><span class="w" id="mwAmk"> </span><span class="mi" id="mwAmo">0</span><span class="p" id="mwAms">)</span> <span class="w" id="mwAmw"> </span><span class="p" id="mwAm0">(</span><span class="nv" id="mwAm4">build-tower</span><span class="w" id="mwAm8"> </span><span class="nv" id="mwAnA">x3</span><span class="w" id="mwAnE"> </span><span class="mi" id="mwAnI">0</span><span class="p" id="mwAnM">)</span> <span class="w" id="mwAnQ"> </span><span class="p" id="mwAnU">(</span><span class="nb" id="mwAnY">print</span><span class="w" id="mwAnc"> </span><span class="nv" id="mwAng">x1</span><span class="w" id="mwAnk"> </span><span class="nv" id="mwAno">nl</span><span class="w" id="mwAns"> </span><span class="nv" id="mwAnw">x2</span><span class="w" id="mwAn0"> </span><span class="nv" id="mwAn4">nl</span><span class="w" id="mwAn8"> </span><span class="nv" id="mwAoA">x3</span><span class="w" id="mwAoE"> </span><span class="nv" id="mwAoI">nl</span><span class="w" id="mwAoM"> </span><span class="nv" id="mwAoQ">nl</span><span class="p" id="mwAoU">)</span> <span class="w" id="mwAoY"> </span><span class="p" id="mwAoc">(</span><span class="nv" id="mwAog">move</span><span class="w" id="mwAok"> </span><span class="vg" id="mwAoo">*max-tower-height*</span><span class="w" id="mwAos"> </span><span class="nv" id="mwAow">x1</span><span class="w" id="mwAo0"> </span><span class="nv" id="mwAo4">x2</span><span class="w" id="mwAo8"> </span><span class="nv" id="mwApA">x3</span><span class="p" id="mwApE">)))</span> <span class="p" id="mwApI">(</span><span class="nv" id="mwApM">hanoi</span><span class="p" id="mwApQ">)</span> <span class="c1" id="mwApU">;;;-------------------------------------------------</span> <span class="p" id="mwApY">)</span><span class="w" id="mwApc"> </span><span class="c1" id="mwApg">;; End of module hanoi</span> <span class="c1" id="mwApk">;;;-------------------------------------------------</span>