twisted.internet.defer

Package twisted :: Package internet :: Module defer

Module twisted.internet.defer

Support for results that aren't immediately available.

API Stability: stable

Classes
`_nothing`
`Deferred`	This is a callback which will be put off until later.
`DeferredList`	I combine a group of deferreds into one callback.

Exceptions
`AlreadyArmedError`
`AlreadyCalledError`
`TimeoutError`

Function Summary
	`_parseDListResult(l, fireOnOneErrback)`
	`execute(callable, args, *kw)` Create a deferred from a callable and arguments.
`Deferred`	`fail(result)` Return a Deferred that has already had '.errback(result)' called.
	`gatherResults(deferredList, fireOnOneErrback)` Returns list with result of given Deferreds.
	`logError(err)`
`Deferred`	`maybeDeferred(f, args, *kw)` Invoke a function that may or may not return a deferred.
	`passthru(arg)`
`Deferred`	`succeed(result)` Return a Deferred that has already had '.callback(result)' called.
	`timeout(deferred)`

Variable Summary
`int`	`FAILURE` = 0
`int`	`SUCCESS` = 1

Function Details

execute(callable, *args, **kw)

Create a deferred from a callable and arguments.

Call the given function with the given arguments. Return a deferred which has been fired with its callback as the result of that invocation or its errback with a Failure for the exception thrown.

fail(result=<class twisted.internet.defer._nothing at 0x82a9674>)

Return a Deferred that has already had '.errback(result)' called.

See succeed's docstring for rationale.

Parameters:: result - The same argument that Deferred.errback takes.

Returns:: Deferred

gatherResults(deferredList, fireOnOneErrback=0)

Returns list with result of given Deferreds.

This builds on DeferredList but is useful since you don't need to parse the result for success/failure.

Parameters:: deferredList
(type=list of Deferreds)

maybeDeferred(f, *args, **kw)

Invoke a function that may or may not return a deferred.

Call the given function with the given arguments. If the returned object is a Deferred, return it. If the returned object is a Failure, wrap it with fail and return it. Otherwise, wrap it in succeed and return it. If an exception is raised, convert it to a Failure, wrap it in fail, and then return it.

Parameters:: f - The callable to invoke
(type=Any callable); args - The arguments to pass to f; kw - The keyword arguments to pass to f

Returns:: The result of the function call, wrapped in a Deferred if necessary.
API Stability: Unstable
(type=Deferred)

succeed(result)

Return a Deferred that has already had '.callback(result)' called.

This is useful when you're writing synchronous code to an asynchronous interface: i.e., some code is calling you expecting a Deferred result, but you don't actually need to do anything asynchronous. Just return defer.succeed(theResult).

See fail for a version of this function that uses a failing Deferred rather than a successful one.

Parameters:: result - The result to give to the Deferred's 'callback' method.

Returns:: Deferred

Variable Details

FAILURE

Type:: int
Value:: 0

SUCCESS

Type:: int
Value:: 1

Generated by Epydoc 2.0 on Sat May 15 20:08:48 2004

http://epydoc.sf.net