improve item list styling; add payload creation form; exend dialog mechanism

1 files changed, 12 insertions, 1 deletions

diff --git a/common/lock.js b/common/lock.js
index 8dd2f5b..f577481 100644
--- a/common/lock.js
+++ b/common/lock.js
@@ -68,9 +68,20 @@ function _lock(lock, cb) {
 
 #EXPORT  lock => new Promise(resolve => _lock(lock, resolve))  AS lock
 
+function try_lock(lock)
+{
+    if (lock.free) {
+	lock.free = false;
+	return true;
+    }
+
+    return false;
+}
+#EXPORT try_lock
+
 function unlock(lock) {
     if (lock.free)
-	throw new Error("Attempting to release a free lock");
+	throw new Exception("Attempting to release a free lock");
 
     if (lock.queue.length === 0) {
 	lock.free = true;