+export let helpDesc =
+`
+clo: clo INPUT_FILE --output-js OUTPUT_JS_FILE
+
+\ta little typesetter powered by TypeScript/Javascript.
+
+## Arguments
+INPUT_FILE\tan input .clo file
+
+## Parameters
+---
+--output-js\tgenerated the output middle JS file
+
+
+Report bugs to: clo@kianting.info
+clo home page: <https://kianting.info/wiki/w/Project:Clo>
+`
+
+processArgv(argv, helpDesc);
+
+/**
+ * processing the passed `argv` (arguments)
+ */
+
+export function processArgv(argv : any, helpDesc : string){
+ let inputFile : string[] = argv['_'];
+ let outputJSFile : string | true = argv['output-js'];
+
+ let NoInputFile : boolean = (inputFile.length == 0);
+ let NoOutputJSFile : boolean = (outputJSFile === undefined || outputJSFile == true);
+ let helpTriggered : boolean = argv['help'];
+
+ if (inputFile.length > 1){
+ console.log("Sorry, the input file should be only one.");
+ }
+
+ /** output --help */
+ if (helpTriggered || NoInputFile || NoOutputJSFile){
+ console.log(helpDesc);