add initial marp implementation with sample content and build configuration

node_modules/speech-rule-engine/js/walker/levels.js

@@ -0,0 +1,57 @@
+"use strict";
+Object.defineProperty(exports, "__esModule", { value: true });
+exports.Levels = void 0;
+class Levels {
+    constructor() {
+        this.level_ = [];
+    }
+    push(level) {
+        this.level_.push(level);
+    }
+    pop() {
+        return this.level_.pop();
+    }
+    peek() {
+        return this.level_[this.level_.length - 1] || null;
+    }
+    indexOf(element) {
+        const last = this.peek();
+        return !last ? null : last.indexOf(element);
+    }
+    find(pred) {
+        const last = this.peek();
+        if (!last) {
+            return null;
+        }
+        for (let i = 0, l = last.length; i < l; i++) {
+            if (pred(last[i])) {
+                return last[i];
+            }
+        }
+        return null;
+    }
+    get(index) {
+        const last = this.peek();
+        return !last || index < 0 || index >= last.length ? null : last[index];
+    }
+    depth() {
+        return this.level_.length;
+    }
+    clone() {
+        const levels = new Levels();
+        levels.level_ = this.level_.slice(0);
+        return levels;
+    }
+    toString() {
+        let str = '';
+        for (let i = 0, level; (level = this.level_[i]); i++) {
+            str +=
+                '\n' +
+                    level.map(function (x) {
+                        return x.toString();
+                    });
+        }
+        return str;
+    }
+}
+exports.Levels = Levels;