1 files changed, 42 insertions, 0 deletions
diff --git a/node_modules/webpack/lib/util/Queue.js b/node_modules/webpack/lib/util/Queue.js
new file mode 100644
index 000000000..ef3ffdc80
--- /dev/null
+++ b/node_modules/webpack/lib/util/Queue.js
@@ -0,0 +1,42 @@
+"use strict";
+
+module.exports = class Queue {
+	constructor(items) {
+		this.first = null;
+		this.last = null;
+		this.length = 0;
+		if(items) {
+			for(const item of items) {
+				this.enqueue(item);
+			}
+		}
+	}
+
+	enqueue(item) {
+		const first = this.first;
+		const node = {
+			item,
+			next: null
+		};
+		if(first === null) {
+			this.last = node;
+		} else {
+			first.next = node;
+		}
+		this.first = node;
+		this.length++;
+	}
+
+	dequeue() {
+		const last = this.last;
+		if(last === null)
+			return undefined;
+		const next = last.next;
+		if(next === null) {
+			this.first = null;
+		}
+		this.last = next;
+		this.length--;
+		return last.item;
+	}
+};