use for-of statements to replace for and for-in

src/core/base.ts

@@ -3,6 +3,68 @@ export type PartialRecord<K extends keyof any, T> = {
     [P in K]?: T;
 }
 
+export function* itemAndIndex<T>(arr: T[]): Iterable<[T, number]> {
+    for (let i = 0; i < arr.length; i++) {
+        yield [arr[i], i] as [T, number];
+    }
+}
+
+export function* reversed<T>(arr: T[]): Iterable<T> {
+    for (let i = arr.length - 1; i >= 0; i--) {
+        yield arr[i] as T;
+    }
+}
+
+export function* reversedItemAndIndex<T>(arr: T[]): Iterable<[T, number]> {
+    for (let i = arr.length - 1; i >= 0; i--) {
+        yield [arr[i], i] as [T, number];
+    }
+}
+
+export function* entries<K extends string | number | symbol, V>(obj: Record<K, V>): Iterable<[K, V]> {
+    for (const key in obj) {
+        if (!Object.prototype.hasOwnProperty.call(obj, key)) {
+            continue;
+        }
+
+        yield [key, obj[key]] as [K, V];
+    }
+}
+
+export function* keys<K extends string | number | symbol, V>(obj: Record<K, V>): Iterable<K> {
+    for (const key in obj) {
+        if (!Object.prototype.hasOwnProperty.call(obj, key)) {
+            continue;
+        }
+
+        yield key as K;
+    }
+}
+
+export function* keysIfValueEquals<K extends string | number | symbol, V>(obj: Record<K, V>, value: V): Iterable<K> {
+    for (const key in obj) {
+        if (!Object.prototype.hasOwnProperty.call(obj, key)) {
+            continue;
+        }
+
+        if (obj[key] !== value) {
+            continue;
+        }
+
+        yield key as K;
+    }
+}
+
+export function* values<K extends string | number | symbol, V>(obj: Record<K, V>): Iterable<V> {
+    for (const key in obj) {
+        if (!Object.prototype.hasOwnProperty.call(obj, key)) {
+            continue;
+        }
+
+        yield obj[key] as V;
+    }
+}
+
 export interface NameValue {
     readonly name: string;
     readonly value: string;

src/core/fiscalyear.ts

@@ -69,8 +69,8 @@ export class FiscalYearStart {
             return undefined;
         }
 
-        const month = parseInt(parts[0], 10);
-        const day = parseInt(parts[1], 10);
+        const month = parseInt(parts[0] as string, 10);
+        const day = parseInt(parts[1] as string, 10);
 
         return FiscalYearStart.of(month, day);
     }
@@ -87,7 +87,7 @@ export class FiscalYearStart {
     }
 
     private static isValidFiscalYearMonthDay(month: number, day: number): boolean {
-        return 1 <= month && month <= 12 && 1 <= day && day <= FiscalYearStart.MONTH_MAX_DAYS[month - 1];
+        return 1 <= month && month <= 12 && 1 <= day && day <= (FiscalYearStart.MONTH_MAX_DAYS[month - 1] as number);
     }
 }
 

src/core/numeral.ts

@@ -96,7 +96,7 @@ export class NumeralSystem implements TypeAndName {
             return '';
         }
 
-        return this.allDigits[digit];
+        return this.allDigits[digit] as string;
     }
 
     public parseInt(value: string): number {
@@ -136,11 +136,11 @@ export class NumeralSystem implements TypeAndName {
         let result = '';
 
         for (let i = 0; i < value.length; i++) {
-            const ch = value[i];
+            const ch = value.charAt(i);
 
             if (NumeralSystem.WesternArabicNumerals.isDigit(ch)) {
-                const digit = NumeralSystem.WesternArabicNumerals.digitsToWesternArabic[ch];
-                result += this.allDigits[digit];
+                const digit = NumeralSystem.WesternArabicNumerals.digitsToWesternArabic[ch] as number;
+                result += this.allDigits[digit] as string;
             } else {
                 result += ch;
             }
@@ -157,11 +157,11 @@ export class NumeralSystem implements TypeAndName {
         let result = '';
 
         for (let i = 0; i < value.length; i++) {
-            const ch = value[i];
+            const ch = value.charAt(i);
 
             if (this.isDigit(ch)) {
-                const digit = this.digitsToWesternArabic[ch];
-                result += NumeralSystem.WesternArabicNumerals.allDigits[digit];
+                const digit = this.digitsToWesternArabic[ch] as number;
+                result += NumeralSystem.WesternArabicNumerals.allDigits[digit] as string;
             } else {
                 result += ch;
             }