cwidget::threads::box< T > Class Template Reference

A higher-level abstraction borrowed from Concurrent Haskell, which borrowed it from another language I forget. More...

#include <threads.h>

Public Member Functions
	box ()
	Create an empty box.
	box (const T &_val)
	Create a box containing the given value.
T	take ()
	Retrieve the current value of this box.
void	put (const T &t)
	Fill this box with a value.
bool	try_take (T &out)
	If there is a value in the box, retrieve it immediately; otherwise do nothing.
bool	try_put (const T &t)
	If the box is empty, place a value in it; otherwise, do nothing.
bool	timed_take (T &out, const timespec &until)
	As try_take(), but wait for the given amount of time before giving up.
bool	timed_put (const T &t, const timespec &until)
	As try_put(), but wait for the given amount of time before giving up.
template<typename Mutator>
void	update (const Mutator &m)
	Atomically modify the contents of the box; if an exception is thrown by the given function object, no action will be performed.

Detailed Description

template<typename T>
class cwidget::threads::box< T >

A higher-level abstraction borrowed from Concurrent Haskell, which borrowed it from another language I forget.

This represents a "box" that can either hold a value or be empty. Any thread can take the current value of the box or place a new value inside it; the attempt will block until a value is available or the box is empty, respectively. It's sort of a single-element bounded communications channel.

The value in the box is stored with copying semantics. Like the other threading primitives, boxes are not copyable.

Member Function Documentation

put()

template<typename T>

void cwidget::threads::box< T >::put ( const T & t )

inline

Fill this box with a value.

If the box is full, block until it is empty.

take()

template<typename T>

T cwidget::threads::box< T >::take ( )

inline

Retrieve the current value of this box.

If the box is empty, block until it is full.

try_put()

template<typename T>

bool cwidget::threads::box< T >::try_put ( const T & t )

inline

If the box is empty, place a value in it; otherwise, do nothing.

Parameters

t	the value to place in the box

Returns

true iff the box was empty (and hence was filled with t)

try_take()

template<typename T>

bool cwidget::threads::box< T >::try_take ( T & out )

inline

If there is a value in the box, retrieve it immediately; otherwise do nothing.

Parameters

out	the location in which the value should be stored

Returns

true iff a value was found in the box

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The documentation for this class was generated from the following file:

• src/cwidget/generic/threads/threads.h