Initial project import

tools/v/vlib/x/async/errors.v

@@ -0,0 +1,24 @@
+module async
+
+// Error strings are centralized because they form the observable contract for
+// callers and tests. Keep them short, stable, and explicit about whether the
+// failure came from x.async or from the parent context.
+const err_group_go_after_wait = 'async: group does not accept new tasks after wait starts'
+const err_group_max_errors_invalid = 'async: group max_errors must be positive'
+const err_group_wait_called = 'async: group wait was already called'
+const err_interval_invalid = 'async: interval must be positive'
+const err_nil_job = 'async: job function is nil'
+const err_periodic_wait_called = 'async: periodic wait was already called'
+const err_pool_closed = 'async: pool is closed'
+const err_pool_queue_full = 'async: pool queue is full'
+const err_pool_queue_size_invalid = 'async: pool queue size must be positive'
+const err_pool_wait_called = 'async: pool wait was already called'
+const err_pool_workers_invalid = 'async: pool worker count must be positive'
+const err_task_wait_called = 'async: task wait was already called'
+const err_timeout = 'async: timeout'
+
+const context_canceled = 'context canceled'
+
+// The current context module exposes deadline expiry as an IError with this
+// message. x.async normalizes that specific deadline error to `async: timeout`.
+const context_deadline_exceeded = 'context deadline exceeded'