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9847e79350
This is a trivial thing, but I found the previous “replace a terminal newline and then count the rest” rather less than obvious. Make the logic more explicit and, as a fun bonus, skip allocating an extra string along the way. (Not that it matters, in this case, but it’s always nice to make that kind of improvement.)
103 lines
2.6 KiB
JavaScript
103 lines
2.6 KiB
JavaScript
// @ts-check
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/**
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* @typedef {{ attr: string, title: string }} FerrisType
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*/
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/** @type {Array<FerrisType>} */
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const FERRIS_TYPES = [
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{
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attr: "does_not_compile",
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title: "This code does not compile!",
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},
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{
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attr: "panics",
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title: "This code panics!",
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},
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{
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attr: "not_desired_behavior",
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title: "This code does not produce the desired behavior.",
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},
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];
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document.addEventListener("DOMContentLoaded", () => {
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for (let ferrisType of FERRIS_TYPES) {
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attachFerrises(ferrisType);
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}
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});
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/**
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* @param {FerrisType} type
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*/
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function attachFerrises(type) {
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let elements = document.getElementsByClassName(type.attr);
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for (let codeBlock of elements) {
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// Skip SVG etc.: in principle, these should never be attached to those, but
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// this means if someone happens to have a browser extension which *is*
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// attaching them, it will not break the code.
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if (!(codeBlock instanceof HTMLElement)) {
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continue;
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}
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let codeLines = codeBlock.innerText;
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let extra = codeLines.endsWith("\n") ? 1 : 0;
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let numLines = codeLines.split("\n").length - extra;
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/** @type {'small' | 'large'} */
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let size = numLines < 4 ? "small" : "large";
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let container = prepareFerrisContainer(codeBlock, size == "small");
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if (!container) {
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continue;
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}
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container.appendChild(createFerris(type, size));
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}
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}
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/**
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* @param {HTMLElement} element - Code block element to attach a Ferris to.
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* @param {boolean} useButtons - Whether to attach to existing buttons.
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* @returns {Element | null} - The container element to use.
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*/
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function prepareFerrisContainer(element, useButtons) {
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let foundButtons = element.parentElement?.querySelector(".buttons");
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if (useButtons && foundButtons) {
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return foundButtons;
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}
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let div = document.createElement("div");
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div.classList.add("ferris-container");
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if (!element.parentElement) {
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console.error(`Could not install Ferris on ${element}, which is missing a parent`);
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return null;
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}
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element.parentElement.insertBefore(div, element);
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return div;
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}
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/**
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* @param {FerrisType} type
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* @param {'small' | 'large'} size
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* @returns {HTMLAnchorElement} - The generated anchor element.
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*/
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function createFerris(type, size) {
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let a = document.createElement("a");
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a.setAttribute("href", "ch00-00-introduction.html#ferris");
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a.setAttribute("target", "_blank");
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let img = document.createElement("img");
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img.setAttribute("src", "img/ferris/" + type.attr + ".svg");
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img.setAttribute("title", type.title);
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img.classList.add("ferris");
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img.classList.add("ferris-" + size);
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a.appendChild(img);
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return a;
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}
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