feat(grid): improve types and name some anonymous functions for bette…

…r debugging

src/grid/functions/at.ts

@@ -1,8 +1,8 @@
 import { createHex, Hex, HexCoordinates } from '../../hex'
-import { GridGeneratorFunction } from '../types'
+import { Traverser } from '../types'
 
-export const at = <T extends Hex>(coordinates: HexCoordinates): GridGeneratorFunction<T> =>
-  function* (currentHex) {
+export const at = <T extends Hex>(coordinates: HexCoordinates): Traverser<T> =>
+  function* next(currentHex) {
     // todo: make createHex accept hex instances or use cloneHex()?
     yield createHex(Object.getPrototypeOf(currentHex), coordinates)
   }

src/grid/functions/move.ts

@@ -1,10 +1,10 @@
 import { createHex, Hex } from '../../hex'
 import { DIRECTION_COORDINATES } from '../constants'
-import { CompassDirection, GridGeneratorFunction } from '../types'
+import { CompassDirection, Traverser } from '../types'
 
 // todo: also accept a string and/or number for direction
-export const move = <T extends Hex>(direction: CompassDirection): GridGeneratorFunction<T> =>
-  function* (currentHex) {
+export const move = <T extends Hex>(direction: CompassDirection): Traverser<T> =>
+  function* next(currentHex) {
     const { q, r } = DIRECTION_COORDINATES[direction]
     const nextCoordinates = { q: currentHex.q + q, r: currentHex.r + r }
     // todo: make createHex accept hex instances or use cloneHex()?

src/grid/functions/repeat.ts

@@ -1,9 +1,9 @@
 import { Hex } from '../../hex'
-import { GridGeneratorFunction } from '../types'
+import { Traverser } from '../types'
 
 // todo: looks a lot like Grid.traverse()
-export const repeat = <T extends Hex>(amount: number, command: GridGeneratorFunction<T>): GridGeneratorFunction<T> =>
-  function* (currentHex) {
+export const repeat = <T extends Hex>(amount: number, command: Traverser<T>): Traverser<T> =>
+  function* next(currentHex) {
     let nextHex = currentHex
     for (let i = 0; i < amount; i++) {
       const hexes = command(nextHex)

src/grid/grid.ts

@@ -1,21 +1,24 @@
 import { equals, Hex, HexCoordinates } from '../hex'
 import { rectangle, RectangleOptions } from './functions'
-import { GridGenerator, GridGeneratorFunction } from './types'
+import { GridGenerator, Traverser } from './types'
+
+interface InternalTraverser<T extends Hex> {
+  (this: Grid<T>): GridGenerator<T>
+}
 
 // eslint-disable-next-line @typescript-eslint/no-empty-function
 function* infiniteTraverser<T extends Hex>(): GridGenerator<T> {}
 
 // fixme: there's a lot of duplicate iteration, use a cache (or memoisation?)
 export class Grid<T extends Hex> {
-  static of<T extends Hex>(hexPrototype: T, traverser?: GridGeneratorFunction<T>) {
+  static of<T extends Hex>(hexPrototype: T, traverser?: InternalTraverser<T>) {
     return new Grid(hexPrototype, traverser)
   }
 
-  constructor(public hexPrototype: T, private traverser: GridGeneratorFunction<T> = infiniteTraverser) {}
+  constructor(public hexPrototype: T, private traverser: InternalTraverser<T> = infiniteTraverser) {}
 
   [Symbol.iterator]() {
-    // todo: {} as T is a bit hacky, but making it an optional parameter is meh
-    return this.traverser({} as T)
+    return this.traverser()
   }
 
   has(coordinates: HexCoordinates) {
@@ -31,7 +34,6 @@ export class Grid<T extends Hex> {
   }
 
   clone(traverser = this.traverser) {
-    // todo: maybe not bind and pass grid to traverser? Tried this, but it results in a "Maximum call stack size exceeded" error
     return Grid.of(this.hexPrototype, traverser.bind(this))
   }
 
@@ -40,33 +42,28 @@ export class Grid<T extends Hex> {
     return this.clone(() => rectangle(this.hexPrototype, options))
   }
 
-  // inspired by https://github.com/ReactiveX/rxjs/blob/master/src/internal/util/pipe.ts
-  // pipe(...fns: GridOperator<T>[]): Grid<T> {
-  //   return ((grid: Grid<T>) => fns.reduce((prev, fn) => fn(prev), grid))(this)
-  // }
-
   // fixme: use generic functions for these kinds of operations
   // something like https://github.com/benji6/imlazy or https://github.com/lodash/lodash/wiki/FP-Guide
   each(fn: (hex: T) => void) {
-    const traverser = function* (this: Grid<T>) {
+    const each: InternalTraverser<T> = function* () {
       for (const hex of this) {
         fn(hex)
         yield hex
       }
     }
-    return this.clone(traverser)
+    return this.clone(each)
   }
 
   map(fn: (hex: T) => T) {
-    const traverser = function* (this: Grid<T>) {
+    const map: InternalTraverser<T> = function* () {
       for (const hex of this) {
         yield fn(hex)
       }
     }
-    return this.clone(traverser)
+    return this.clone(map)
   }
 
-  // todo: other/more args?
+  // todo: alias to take or takeUntil?
   run(stopFn: (hex: T) => boolean = () => false) {
     for (const hex of this) {
       if (stopFn(hex)) {
@@ -76,14 +73,13 @@ export class Grid<T extends Hex> {
     return this // or clone()? todo: when to return clone and when not?
   }
 
-  traverse(...commands: GridGeneratorFunction<T>[]) {
+  traverse(...commands: Traverser<T>[]) {
     if (commands.length === 0) {
       return this // or clone()? todo: when to return clone and when not?
     }
-    // todo: {} as T is a bit hacky, but making it an optional parameter is meh
-    let currentHex = this.traverser({} as T).next().value || ({ q: 0, r: 0 } as T)
+    let currentHex = this.traverser().next().value || ({ q: 0, r: 0 } as T)
 
-    const traverser = function* (this: Grid<T>) {
+    function* traverse(this: Grid<T>) {
       for (const command of commands) {
         const hexes = command(currentHex)
         for (const hex of hexes) {
@@ -96,6 +92,6 @@ export class Grid<T extends Hex> {
         }
       }
     }
-    return this.clone(traverser)
+    return this.clone(traverse)
   }
 }

src/grid/types.ts

@@ -22,6 +22,6 @@ export type CompassDirection = PointyCompassDirection | FlatCompassDirection
 
 export type GridGenerator<T extends Hex> = Generator<T, void>
 
-export interface GridGeneratorFunction<T extends Hex> {
+export interface Traverser<T extends Hex> {
   (currentHex: T): GridGenerator<T>
 }