Boost C++ Libraries

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Unbounded Sequence

Description

A Unbounded Sequence allows Out-of-Bounds access: it will achieve something like a Window Function. Most of the sequences do not meet this concept, but some special usecases do.

	Important
	User extending sequences should handle any parameters or be SFINAE-friendly.

Notation

s: An Fusion Sequence
S: An Fusion Sequence type
M: An MPL integral constant
N: An integral constant
K: An arbitrary key type
o: An arbitrary object
e: A Sequence element

Valid Expressions

Expression	Return type	Type Requirements	Runtime Complexity
`at_c<N>(s)`	Any type		Depends on its traversability
`at_c<N>(s) = o`	Any type		Depends on its traversability
`at<M>(s)`	Any type		Depends on its traversability
`at<M>(s) = o`	Any type		Depends on its traversability
`at_key<K>(s)`	Any type	`S` should be Associative Sequence	Depends on its traversability
`at_key<K>(s) = o`	Any type	`S` should be Associative Sequence	Depends on its traversability

Result Type Expressions

Expression	Compile Time Complexity
`result_of::at<S, M>::type`	Depends on its traversability
`result_of::at_c<S, N>::type`	Depends on its traversability
`result_of::value_at<S, M>::type`	Depends on its traversability
`result_of::value_at_c<S, N>::type`	Depends on its traversability
`result_of::at_key<S, K>::type`	Depends on its traversability
`result_of::value_at_key<S, K>::type`	Depends on its traversability

Models

none.