starting to split options by type

lib/Options/BaseOption.ts

@@ -0,0 +1,45 @@
+import { OptionSource } from '../Sources/OptionSource';
+import { Option } from '../Option';
+import { EnvSource } from '../Sources/EnvSource';
+import { ErrorCallback } from '../ErrorCallback';
+import { ArgSource } from '../Sources/ArgSource';
+import { ConfigSource } from '../Sources/ConfigSource';
+import { TypeValidation } from '../TypeValidation/TypeValidation';
+
+export abstract class BaseOption<T> {
+  protected readonly sources: OptionSource[] = [];
+  private _config: Option;
+
+  public constructor (
+    config: Option,
+    error_callback?: ErrorCallback,
+    exit_on_interrupt = true
+  ) {
+    this._config = config;
+
+    const sources = config.sources || {};
+    if (typeof sources.configs !== 'undefined')
+      this.sources.push (new ConfigSource (sources.configs, error_callback));
+
+    if (sources.env !== false)
+      this.sources.push (new EnvSource (error_callback));
+
+    if (sources.console !== false)
+      this.sources.push (new ArgSource (error_callback));
+
+    if (sources.interactive !== false) {
+      this.sources.push (new InteractiveSource (
+        exit_on_interrupt,
+        error_callback
+      ));
+    }
+  }
+
+  protected abstract get validation(): TypeValidation;
+
+  public async parse(): Promise<T> {
+    for (let source of this.sources) {
+      source.parse(this._config);
+    }
+  };
+}

lib/Options/StringOption.ts

@@ -0,0 +1,14 @@
+import { Option } from '../Option';
+import { BaseOption } from './BaseOption';
+
+export class StringOption extends BaseOption<string> {
+  private _config: Option;
+
+  public constructor (config: Option) {
+    this._config = config;
+  }
+
+  public async parse (): Promise<string> {
+
+  }
+}