Created classes and methods needed to create Sequential Identifiers

src/file/paragraph/run/sequential-identifier-instruction.ts

@@ -0,0 +1,19 @@
+// http://officeopenxml.com/WPfieldInstructions.php
+import { XmlAttributeComponent, XmlComponent } from "file/xml-components";
+
+enum SpaceType {
+    DEFAULT = "default",
+    PRESERVE = "preserve",
+}
+
+class TextAttributes extends XmlAttributeComponent<{ space: SpaceType }> {
+    protected xmlKeys = { space: "xml:space" };
+}
+
+export class SequentialIdentifierInstruction extends XmlComponent {
+    constructor(identifier: string) {
+        super("w:instrText");
+        this.root.push(new TextAttributes({ space: SpaceType.PRESERVE }));
+        this.root.push(`SEQ ${identifier}`);
+    }
+}