Fix: fix small typing issues

src/Models/Denomination.ts

@@ -64,7 +64,7 @@ export class Denomination {
             throw `${context} uses the old 'default'-key. Use "useIfNoUnitGiven" or "useAsDefaultInput" instead`
         }
 
-        const humanTexts = typeof json.human === "string" ? Translations.T(json.human) : new Translation(json.human)
+        const humanTexts: TypedTranslation<{ quantity: string }> = Translations.T(json.human)
         humanTexts.OnEveryLanguage((text, language) => {
             if (text.indexOf("{quantity}") < 0) {
                 throw `In denomination: a human text should contain {quantity} (at ${context}.human.${language}). The offending text is: ${text}`
@@ -85,21 +85,6 @@ export class Denomination {
         )
     }
 
-    public clone() {
-        return new Denomination(
-            this.canonical,
-            this._canonicalSingular,
-            this.useIfNoUnitGiven,
-            this.prefix,
-            this.addSpace,
-            this.alternativeDenominations,
-            this.human,
-            this.humanSingular,
-            this.validator,
-            this.factorToCanonical
-        )
-    }
-
     public withBlankCanonical() {
         return new Denomination(
             "",
@@ -181,18 +166,17 @@ export class Denomination {
         }
 
         value = value.toLowerCase()
-        const self = this
 
-        function startsWith(key) {
-            if (self.prefix) {
+        const startsWith = (key) => {
+            if (this.prefix) {
                 return value.startsWith(key)
             } else {
                 return value.endsWith(key)
             }
         }
 
-        function substr(key) {
-            if (self.prefix) {
+        const substr = (key) => {
+            if (this.prefix) {
                 return value.substring(key.length).trim()
             }
             let trimmed = value.substring(0, value.length - key.length).trim()