ErrLookup › ruby-concurrency/concurrent-ruby

ruby-concurrency/concurrent-ruby

Modern concurrency tools including agents, futures, promises, thread pools, supervisors, and more. Inspired by Erlang, Clojure, Scala, Go, Java, JavaScript, and classic concurrency patterns. · Ruby · 229 source files

Analyzed at 0b88d5ff75 on 2026-08-21. 77 documented errors.

Code / MessageTypeSeverityTags
Value (# ) '# ' # any of: # .
exception error concurrent-ruby, concurrent-ruby-edge, typecheck, typeerror, actor
:class option is ignored when calling on context class, use…
exception error concurrent-ruby, concurrent-ruby-edge, actor, spawn, argumenterror, options
probe is not Resolvable
exception error concurrent-ruby, concurrent-ruby-edge, erlang-actor, ask, promises, argumenterror
Could not initialize intrinsics
exception critical java, sun-misc-unsafe, security-manager, jvm, class-init, concurrent-ruby, jruby
Concurrent::RejectedExecutionError
exception error concurrency, ruby, thread-pool, backpressure, executor-queue
NullPointerException
exception error null-key, null-value, putall, bulk-copy, concurrent-map, jruby
Too many writer threads
exception critical concurrent-ruby, read-write-lock, deadlock, resource-limit
IllegalStateException
exception error iterator, illegal-state, traverser, concurrent-map, remove
Cannot release a write lock which is not held
exception error concurrent-ruby, reentrantreadwritelock, illegaloperationerror, lock-release, write-lock
Concurrent::Agent::ValidationError
exception error concurrent-ruby, agent, restart, validation-error
Concurrent::TimeoutError
exception error concurrent-ruby, agent, timeout, await
should pass observer as a first argument or block
exception error concurrent-ruby, observer, observable, copy-on-write, argumenterror
environment has to be a class inheriting from Environment…
exception error concurrent-ruby, concurrent-ruby-edge, erlang-actor, environment, argumenterror
bad options #
exception error concurrent-ruby, concurrent-ruby-edge, erlang-actor, demonitor, argumenterror, options
Update failed
exception error concurrent-ruby, atomic-reference, concurrentupdateerror, cas, optimistic-concurrency, verbose
Cannot release a read lock which is not held
exception error concurrent-ruby, reentrantreadwritelock, illegaloperationerror, lock-release
Cannot release a write lock which is not held by the…
exception error concurrent-ruby, readwritelock, illegaloperationerror, lock-ownership, threading
Recursive call to #value during evaluation of the Delay
exception error concurrency, ruby, lazy-initialization, recursion, deadlock
size must be greater than 0
exception error ruby, concurrent-ruby, channel, buffer, argumenterror, capacity
`min_threads` cannot be less than #
exception error ruby, concurrency, thread-pool, argument-validation, configuration
Required array size too large
exception critical jruby, java, concurrent-hash-map, out-of-memory, array-limits, concurrency
Cannot use both value and block as default value
exception error concurrent-ruby, fiberlocalvar, argumenterror, default-value
returned value # is not a Future
exception error ruby, concurrency, promises, flatmap, typeerror
seconds must be greater than zero
exception error ruby, concurrency, scheduled-task, argument-error, time-handling
Too many reader holds on this thread
exception error concurrent-ruby, reentrant-lock, recursion, resource-limit
only one of block or value can be supplied
exception error concurrent-ruby, concurrent-ruby-edge, erlang-actor, receive, argumenterror
cannot give arguments and a block
exception error concurrent-ruby, observer, notify, argumenterror
wrong number of arguments
exception error concurrent-ruby, async, arity, argumenterror
can't set a timeout if non_block is enabled
exception error concurrent-ruby, timeout-queue, queue, argumenterror
# is greater than the maximum value of #
exception error ruby, concurrency, atomic, range-error, integer-overflow
must be greater than zero
exception error ruby, concurrency, timer-task, argument-error, interval-validation
Too many reader threads
exception error concurrent-ruby, reentrant-lock, read-write-lock, resource-limit, lock-leak
identifier # needs to be constant
exception error ruby, struct, abstract-struct, name-error, constant-naming
supported only on root promise
exception error ruby, concurrency, promise, state-machine, api-misuse
`synchronous` cannot be set unless `max_queue` is 0
exception error ruby, jruby, concurrency, thread-pool, argument-error, configuration
must set with either a value or a block
exception error ruby, concurrency, ivar, write-once, argument-validation
cannot provide both an observer and a block
exception error concurrent-ruby, observer, add-observer, argumenterror
Not all dependencies are IVars. Dependencies: #
exception error ruby, concurrency, dataflow, argument-error, type-mismatch
executor not recognized by '#
exception error ruby, concurrency, executor, argumenterror, configuration
wrong number of arguments (0 for 1+)
exception error ruby, struct, settable-struct, argument-error, factory-method
Concurrent::MultipleAssignmentError
exception error concurrency, ruby, ivar, write-once, race-condition
no block given
exception error ruby, concurrency, scheduled-task, argument-error, missing-block
offset # too large for struct(size:# )
exception error ruby, struct, settable-struct, index-error, bounds-check
ImmediateExecutor is not supported
exception error ruby, concurrency, actor, executor, argument-error, concurrent-ruby-edge
`max_threads` cannot be greater than #
exception error ruby, jruby, concurrency, thread-pool, argument-error, configuration, integer-overflow
can't dump hash with default proc
exception error ruby, serialization, marshal, concurrent-map, default-proc
it is not rejected
exception error ruby, concurrency, promises, future, state-machine
rescuers and block are both missing
exception error ruby, concurrency, promise, block-argument, argument-validation
IllegalArgumentException
exception error constructor, capacity, illegal-argument, validation
no member '# ' in struct
exception error ruby, struct, settable-struct, name-error, unknown-member
`min_threads` cannot be more than `max_threads`
exception error ruby, concurrency, thread-pool, argument-validation, configuration
# is not an Integer
exception error ruby, concurrency, atomic, argument-error, type-coercion
wrong number of arguments
exception error concurrent-ruby, async, arity, varargs, argumenterror
capacity must be at least 1 for this buffer type
exception error ruby, concurrent-ruby, channel, buffer, argumenterror, capacity
# is less than the maximum value of #
exception error ruby, concurrency, atomic, range-error, integer-underflow
# cannot be negative
exception error ruby, concurrency, semaphore, countdown-latch, argument-error, validation
interval_type must be either :fixed_delay or :fixed_rate
exception error ruby, concurrency, timer-task, argument-error, config-validation
unbuffered channels cannot have a capacity
exception error ruby, concurrent-ruby, channel, buffer, argumenterror, goroutine-channels
:load_factor must be a number between 0 and 1
exception error ruby, concurrent-map, argumenterror, constructor-validation, configuration
an executor must be provided
exception error concurrent-ruby, dataflow, executor, argumenterror
# is not a valid fallback policy
exception error ruby, jruby, concurrency, executor, argument-error, configuration
# cannot be negative or zero
exception error ruby, concurrency, cyclic-barrier, argument-error, validation
struct size differs
exception error ruby, struct, abstract-struct, argument-error, arity-mismatch
agent is not failed
exception error ruby, concurrent-ruby, agent, state-machine, error-recovery
key not found
exception error ruby, concurrent-map, keyerror, fetch, race-condition
cannot enqueue nil
exception error concurrent-ruby, priority-queue, nil, jruby, argumenterror
ArgumentError
exception error ruby, concurrency, promises, arity, argumenterror
:initial_capacity must be a positive Integer
exception error ruby, concurrent-map, argumenterror, constructor-validation, configuration
unrecognized error mode
exception error ruby, concurrent-ruby, agent, argumenterror, options, enum
levels has to be higher than 0
exception error ruby, concurrency, promises, argumenterror, validation
provide only a value or a block
exception error ruby, concurrency, ivar, argument-validation, constructor
number of threads must be greater than zero
exception error ruby, concurrency, thread-pool, executor, argument-error, configuration
no action given
exception error ruby, concurrent-ruby, agent, nil-safety, argumenterror
timeout must 0.0 or more
exception error ruby, concurrent-ruby, selector, timeout, argumenterror, monotonic-time
invalid action
exception error ruby, concurrent-ruby, selector, channel, argumenterror, enum
`max_threads` cannot be less than #
exception error ruby, jruby, concurrency, thread-pool, argument-error, configuration
only one error handler allowed
exception error ruby, concurrent-ruby, selector, error-handling, argumenterror