return types in typescript

script/gallery.ts

@@ -10,14 +10,14 @@ let showSingles = false;
 
 
 function fillSets(): [Set<string>, Set<string>] {
-  function checkedValues(boxes: Boxes) {
+  function checkedValues(boxes: Boxes): Set<string> {
     return new Set([...boxes].filter(b => b.checked).map(b => b.value));
   }
 
   return [checkedValues(reqBoxes), checkedValues(excBoxes)];
 }
 
-function updateItems() {
+function updateItems(): void {
   const [reqTags, excTags] = fillSets();
   const anyReq = reqTags.size > 0;
 
@@ -37,7 +37,7 @@ function updateItems() {
     if (marker !== null) marker.hidden = hideMarker;
   }
 
-  function disp(pfx: string, tags: Iterable<string>) {
+  function disp(pfx: string, tags: Iterable<string>): string {
     return [...tags].map(x => pfx + x).join('\u2003'); // em space
   }
   const plus  = disp('+\u2009', reqTags); // thin space
@@ -46,12 +46,12 @@ function updateItems() {
     `${plus}\u2003${minus}`.trim();
 }
 
-function update() {
+function update(): void {
   updateItems();
   history.pushState(null, "", makeFragment());
 }
 
-function converseId(id: string) {
+function converseId(id: string): string {
   if (id.match(/^require/)) {
     return id.replace('require', 'exclude');
   } else {
@@ -59,7 +59,7 @@ function converseId(id: string) {
   }
 }
 
-function toggle(checkbox: HTMLInputElement) {
+function toggle(checkbox: HTMLInputElement): void {
   if (checkbox.checked) {
     const converse = document.getElementById(converseId(checkbox.id)) as HTMLInputElement;
     converse.checked = false;
@@ -68,17 +68,17 @@ function toggle(checkbox: HTMLInputElement) {
 }
 
 
-function clearForm() {
+function clearForm(): void {
   allBoxes.forEach(b => b.checked = b.defaultChecked);
 }
 
-function clear(e: Event) {
+function clear(e: Event): void {
   clearForm();
   update();
   e.preventDefault();
 }
 
-function toggleSingles(e: Event) {
+function toggleSingles(e: Event): void {
   showSingles = !showSingles;
 
   const elems = Array.from(document.querySelectorAll('.filterlist li')) as HTMLElement[];
@@ -94,7 +94,7 @@ function toggleSingles(e: Event) {
 }
 
 
-function makeFragment() {
+function makeFragment(): string {
   const allBoxesArr = Array.from(allBoxes);
   const ids = allBoxesArr.filter(b => b.checked).map(b => b.id);
   if (ids.length == 0) {
@@ -107,7 +107,7 @@ function makeFragment() {
 }
 
 
-type Shortcuts = { [short: string]: Set<string> };
+type Shortcuts = Record<string, Set<string>>;
 const shortcuts: Shortcuts = {
   summary:        new Set(['require_artsummary']),
   colourexamples: new Set(['require_colourexample']),
@@ -120,7 +120,7 @@ const shortcuts: Shortcuts = {
   kesi:           new Set(['require_kesi']),
 };
 
-function useFragment() {
+function useFragment(): void {
   const frag = decodeURIComponent(location.hash).replace(/^#/, '');
   const details = document.getElementById('filters-details') as HTMLDetailsElement;
   const fromShortcut = shortcuts[frag];
@@ -145,8 +145,8 @@ function useFragment() {
 }
 
 
-function sortFilters(cmp: (a: Node, b: Node) => number) {
-  function sort1(id: string) {
+function sortFilters(cmp: (a: Node, b: Node) => number): void {
+  function sort1(id: string): void {
     const elt = document.getElementById(id);
     if (elt === null) return;
 
@@ -162,7 +162,7 @@ function sortFilters(cmp: (a: Node, b: Node) => number) {
   sort1('exclude');
 }
 
-function sortFiltersAlpha(e: Event) {
+function sortFiltersAlpha(e: Event): void {
   function getName(node: Node): string {
     if (node instanceof Element) {
       return node.getElementsByTagName('input')[0]?.value ?? '';
@@ -174,7 +174,7 @@ function sortFiltersAlpha(e: Event) {
   e.preventDefault();
 }
 
-function sortFiltersUses(e: Event) {
+function sortFiltersUses(e: Event): void {
   function getUses(node: Node): number {
     if (node instanceof Element) {
       const countStr = node.getElementsByTagName('label')[0]?.dataset.count;
@@ -188,7 +188,7 @@ function sortFiltersUses(e: Event) {
 }
 
 
-function setup() {
+function setup(): void {
   function inputs(id: string): Boxes {
     const iter = document.getElementById(id)!.getElementsByTagName('input');
     return new Set(Array.from(iter));
@@ -216,7 +216,7 @@ function setup() {
 
   allBoxes.forEach(b => b.addEventListener('change', () => toggle(b)));
 
-  function addClick(id: string, f: (e: Event) => void) {
+  function addClick(id: string, f: (e: Event) => void): void {
     document.getElementById(id)!.addEventListener('click', f);
   }
   addClick('clear',     clear);

script/nsfw-warning.ts

@@ -1,12 +1,12 @@
 const nsfwOk = 'nsfw-ok';
 const dialog = document.getElementById('nsfw-dialog')! as HTMLDialogElement;
 
-function yes() {
+function yes(): void {
   localStorage.setItem(nsfwOk, '1');
   dialog.close();
 }
 
-function setup() {
+function setup(): void {
   if (!localStorage.getItem(nsfwOk)) {
     (dialog.querySelector('#nsfw-yes') as HTMLElement).onclick = yes;
     // nsfw-no is a normal link

script/single.ts

@@ -28,7 +28,7 @@ function setImage(id: string, src: string, href: string,
 
   if (curCw && !coverNew) {
     // keep old cover until load
-    function removeCover() { setTimeout(() => openCW(null, curCw!), 100); }
+    function removeCover(): void { setTimeout(() => openCW(null, curCw!), 100); }
     mainimg.addEventListener('load', removeCover, {once: true});
   } else if (coverNew) {
     // place new cover
@@ -82,7 +82,7 @@ function useFragment(firstLoad = false): void {
   }
 }
 
-function setup() {
+function setup(): void {
   mainfig  = document.getElementById('mainfig')!;
   mainimg  = document.getElementById('mainimg') as HTMLImageElement;
   mainlink = document.getElementById('mainlink') as HTMLAnchorElement;