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import { getById, div, span, h, writeError } from "/common.module.js"
export function onLoad() {
console.log('Loaded');
const form = getById("form");
const input = getById("input");
const log = getById("log");
form.addEventListener("submit", submitForm);
const urlParams = new URLSearchParams(window.location.search);
const queryInput = urlParams.get('in');
if (input.value.length === 0) {
input.value = queryInput;
}
}
export function onUpdate() {
console.log('Updated');
}
export function onDispose() {
console.log('Disposed');
}
/** @param {SubmitEvent} event */
function submitForm(event) {
console.log(input.value);
resetLog();
try {
const stack = evalString(input.value);
console.log(stack);
const path = window.location.pathname;
const params = new URLSearchParams(window.location.search);
const hash = window.location.hash;
params.set("in", input.value);
window.history.replaceState({}, '', `${path}?${params.toString()}${hash}`);
}
catch (error) {
writeError(error);
}
event.preventDefault();
}
/** @param {string} input */
function evalString(input) {
let words = input.trim().split(' ').filter(i => i);
return evalWords([], words);
}
function effect2(f) {
return (stack) => {
if (stack.length <= 1) throw "stack underflow";
let [x, y, ...rest] = stack;
return [f(y, x), ...rest];
}
}
const plus = effect2((a, b) => a + b);
const subtract = effect2((a, b) => a - b);
const multiply = effect2((a, b) => a * b);
const divide = effect2((a, b) => a / b);
function evalWords(stack, words) {
writeLog(stack, words);
if (words.length === 0) return stack;
let [word, ...rest] = words;
return evalWords(evalWord(word, stack), rest);
}
function evalWord(word, stack, rest) {
switch (word) {
case "+": return plus(stack);
case "-": return subtract(stack);
case "*": return multiply(stack);
case "/": return divide(stack);
case "dup": return dup(stack);
case "drop": return drop(stack);
case "swap": return swap(stack);
default: return parse(word, stack);
}
}
function dup(stack) {
let [x, ...rest] = stack;
return [x, x, ...rest];
}
function drop(stack) {
let [_, ...rest] = stack;
return rest;
}
function swap(stack) {
let [x, y, ...rest] = stack;
return [y, x, ...rest];
}
function parse(word, stack) {
let num = Number(word);
if (isNaN(num)) {
throw `word '${word}' not recognised`;
}
return [num, ...stack];
}
function writeLog(stack, words) {
let log_left = span(`[${stack.join(', ')}]`);
let log_right = span(words.join(' '));
if (words.length === 0) {
log_left.textContent += " <=="
}
let log_row = div(log_left, log_right);
log_row.className = "flex-spread";
log.appendChild(log_row);
}
function resetLog() {
if (!log.hasChildNodes()) return;
let summary = h("summary");
summary.textContent = log.firstChild.lastChild.textContent;
let old_log = log.cloneNode(true);
old_log.id = '';
let details = h("details", summary, old_log);
details.className = "history"
log.insertAdjacentElement("afterend", details);
log.replaceChildren(); //remove children, clear log
}
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