From af5662781840ac45c21cbf14cbc7973bcf39d1da Mon Sep 17 00:00:00 2001 From: Adrian Kummerlaender Date: Tue, 17 Feb 2015 22:47:56 +0100 Subject: Reimplemented `TakeWhile` and `DropWhile` in terms of `ListIndex` * new higher order list operation `ListIndex` returns the index of the first list element satisfying a given predicate function ** this enables finding the split index required for both `TakeWhile` and `DropWhile` ** actual list manipulation is then performed using lower order `Take` or `Drop` ** analogously to `list-index` in SRFI-1 ** added appropriate test case * added higher order predicate utility function `utility::predicate_assurance` ** as its name implies this function enables assuring that a value satisfies a given predicate *** if this is not the case a surrogate value is returned instead ** this is used to return a appropriate size value if the `ListIndex` call fails because no element satisfies its predicate ** `detail::predicate_negator` was moved from `Remove`'s implementation details into the newly introduced `utility` namespace *** as it is required by both `TakeWhile` and `DropWhile` in addition to `Remove` * continuation of 8e49cc6 --- src/list/operation/higher/remove.h | 13 ++----------- 1 file changed, 2 insertions(+), 11 deletions(-) (limited to 'src/list/operation/higher/remove.h') diff --git a/src/list/operation/higher/remove.h b/src/list/operation/higher/remove.h index 598f5a6..6770359 100644 --- a/src/list/operation/higher/remove.h +++ b/src/list/operation/higher/remove.h @@ -2,25 +2,16 @@ #define TYPEASVALUE_SRC_LIST_OPERATION_HIGHER_REMOVE_H_ #include "filter.h" +#include "utility/predicate.h" namespace tav { -namespace detail { - -template class Predicate> -struct predicate_negator { - template - using function = Not>; -}; - -} - template < template class Predicate, typename List > using Remove = Filter< - detail::predicate_negator::template function, + utility::predicate_negator::template function, List >; -- cgit v1.2.3