Telematica ass2: Added '--help' option.

telematica/ass2/translate

@@ -4,11 +4,14 @@
 // Call Google Translate API
 function translate($text, $from, $to) {
     $key = "AIzaSyD5sFp2R2IMtDVWdu-4X-TptJCSod0chVc";
-    $url = sprintf("https://www.googleapis.com/language/translate/v2?key=%s&source=%s&target=%s&q=%s",
-                   $key, $from, $to, urlencode($text));
+    $url = sprintf("https://www.googleapis.com/language/translate/v2?"
+        ."key=%s&source=%s&target=%s&q=%s", $key, $from, $to, urlencode($text));
 
-    if( ($response = file_get_contents($url)) === false )
-        die("Cannot connect to Google Translate server.");
+    if( ($response = @file_get_contents($url)) === false ) {
+        die("Got negative response from Google Translate server.\n"
+            ."Check your internet connection and make sure that you "
+            ."entered valid language codes.\n");
+    }
 
     $response = json_decode($response, true);
 
@@ -16,7 +19,17 @@ function translate($text, $from, $to) {
 }
 
 // Parse input
-$argc != 3 && die(sprintf("Usage: %s FROM TO\n", $argv[0]));
+if( $argc != 3 ) {
+    echo sprintf("Usage: %s FROM TO\n", $argv[0]);
+
+    if( $argv[1] == "--help" ) {
+        echo "FROM is the input language, TO is the language to translate to.\n"
+            ."Both languages should be entered as a 2-character long code.\n";
+    }
+
+    exit;
+}
+
 list($from, $to) = array_slice($argv, 1);
 $lang_format = "/^[a-z]{2}$/i";