(feature) add StringAsDefaultValue. Closes #40

src/post-processors/string-as-default-value.post-processor.ts

@@ -0,0 +1,16 @@
+import { TranslationCollection } from '../utils/translation.collection';
+import { PostProcessorInterface } from './post-processor.interface';
+
+interface Options {
+	defaultValue: string;
+}
+
+export class StringAsDefaultValuePostProcessor implements PostProcessorInterface {
+	public name: string = 'StringAsDefaultValue';
+
+	public constructor(protected options: Options) {}
+
+	public process(draft: TranslationCollection, extracted: TranslationCollection, existing: TranslationCollection): TranslationCollection {
+		return draft.map((key, val) => (existing.get(key) === undefined ? this.options.defaultValue : val));
+	}
+}