Selector Namespace Reference

Typedefs
using	selector_t = size_t()
	The type of an Initializer's Selector function.

Functions
std::function< selector_t >	select (size_t n)
std::function< selector_t >	random (size_t a, size_t b)
std::function< selector_t >	random (size_t n)
template<size_t FLAG = NO_SELECTION_INDEX>
std::function< selector_t >	skippable (std::function< selector_t > selector)
std::function< selector_t >	timeout (std::function< selector_t > selector, uint64_t microsec, unsigned int fallback=NO_SELECTION_INDEX, std::function< void(size_t)> cancel=nullptr)
std::function< selector_t >	delayed (std::function< selector_t > selector, unsigned int ms)
std::function< selector_t >	potentiometer (vex::pot &potentiometer, const size_t &initializations)
std::function< selector_t >	weighted_potentiometer (vex::pot &potentiometer, std::vector< Initialization > &initializations)

Variables
constexpr size_t	NO_SELECTION_INDEX = SIZE_MAX
	A constant index that is used in selector functions to represent when a selection has not yet been made.

Detailed Description

A namespace containing predefined selector functions and wrappers that can be passed to an Initializer.

Function Documentation

delayed()

std::function< selector_t > Selector::delayed ( std::function< selector_t > selector, unsigned int ms )

inline

A selector function wrapper that delays the program for a set amount of time before selecting the Initialization.

Parameters

selector	The selector function to execute
ms	The amount of time to delay for, in milliseconds

Returns

The return value of selector

potentiometer()

std::function< selector_t > Selector::potentiometer ( vex::pot & potentiometer, const size_t & initializations )

inline

A selector function that utilizes a potentiometer to select the Initialization Each initialization is corresponds to an equal percentage of the potentiometer's range.

Parameters

potentiometer	The potentiometer to select inputs based on
initializations	The number of initializations

Returns

A selector function that selects its Initialization based utilizing a potentiometer

random() [1/2]

std::function< selector_t > Selector::random ( size_t a, size_t b )

inline

Returns a selector function that selects a random Initialization

Precondition

Call srand() in pre-initialization using the VEX Brain's high-resolution timer

Parameters

a	The inclusive beginning of the random range
b	The exclusive end of the random range

Returns

A random size_t value in the range [A,B). If the range is invalid (B

random() [2/2]

std::function< selector_t > Selector::random ( size_t n )

inline

Returns a selector function that selects a random Initialization

Precondition

Call srand() in pre-initialization using the VEX Brain's high-resolution timer

Parameters

n	The exclusive end of the random range

Returns

A random size_t value in the range [0,N).

select()

std::function< selector_t > Selector::select ( size_t n )

inline

Returns a selector function that selects the Initialization corresponding to N

Parameters

n	The Initialization to select

Returns

The value of N

skippable()

template<size_t FLAG = NO_SELECTION_INDEX>

std::function< selector_t > Selector::skippable ( std::function< selector_t > selector )

inline

Returns a selector function wrapper that allows selection to be skipped based on a compile-time flag. This should only be used for debugging, as it would otherwise defeat the purpose of the Initializer.

Template Parameters

FLAG	The Initialization to select if compile-time selection is wanted, or nothing to select Initializations based on the provided selector.

Parameters

selector

The selector function for runtime selection

Returns

The compile selector function if flag is defined, and the selector argument if flag is not defined

timeout()

std::function< selector_t > Selector::timeout ( std::function< selector_t > selector, uint64_t microsec, unsigned int fallback = NO_SELECTION_INDEX, std::function< void(size_t)> cancel = nullptr )

inline

A selector function wrapper that allows a selection to timeout, returning the fallback if it does.

Precondition

The selector function must be thread-safe

Parameters

selector	The thread-safe selector function to execute
microsec	The amount of time until a timeout occurs, in microseconds
fallback	The return value if a timeout occurs
cancel	The callback used to notify the rest of the program if a timeout occured. It will always be passed the fallback value as its argument.

Returns

The return value of selector, or fallback if a timeout occurs

weighted_potentiometer()

std::function< selector_t > Selector::weighted_potentiometer ( vex::pot & potentiometer, std::vector< Initialization > & initializations )

inline

A selector function that utilizes a potentiometer to select the Initialization. This function uses the metadata of the Initializations to determine their representation on the potentiometer.

Parameters

potentiometer	The potentiometer to select inputs based on
initializations	A vector of initializations

Returns

A selector function that selects its Initialization based utilizing a potentiometer