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>

List of all members.

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.

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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.

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Constructor & Destructor Documentation

template<typename T>

cwidget::threads::box< T >::box

(

)

[inline]

Create an empty box.

template<typename T>

cwidget::threads::box< T >::box

(

const T &

_val

)

[inline]

Create a box containing the given value.

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Member Function Documentation

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.

References cwidget::threads::condition::wait().

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.

References cwidget::threads::condition::wait(), and cwidget::threads::condition::wake_one().

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

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)

References cwidget::threads::condition::wake_one().

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

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