1 files changed, 19 insertions, 0 deletions
diff --git a/generator/util.js b/generator/util.js
new file mode 100644
index 0000000..e9b5c78
--- /dev/null
+++ b/generator/util.js
@@ -0,0 +1,19 @@
+//Copyright Chris Xiong 2019
+//License: Expat (MIT)
+module.exports={
+	mtime_cmp:function(a,b){return _mtime_cmp(a,b);}
+};
+const fs=require('fs');
+
+/*Returns true when file b exists and has a mtime no earlier than file a,
+ *false otherwise.
+ */
+function _mtime_cmp(a,b)
+{
+	const mtimea=fs.statSync(a).mtimeMs;
+	let mtimeb=0;
+	try{
+		mtimeb=fs.statSync(b).mtimeMs;
+	}catch(e){return false};
+	return mtimeb>=mtimea;
+}