solver::SolverDictWrapper Class Reference

A type erased wrapper around a particular solver dictionary implementation. More...

#include <solver.hpp>

Public Member Functions
template<class SolverDict , class Words >
	SolverDictWrapper (const SolverDict &solver_dict, Words &&words)
	SolverDictWrapper (SolverDictWrapper &&)=default
SolverDictWrapper &	operator= (SolverDictWrapper &&)=default
std::size_t	size () const
	The number of whole words in this dictionary.
bool	empty () const
	Checks if this dictionary is empty.
bool	contains (const std::string_view word) const
	Check if this dictionary contains word. More...
bool	further (const std::string_view word) const
	Check if this dictionary might contain words with word as a prefix. More...
template<class OutputIndexIterator >
void	contains_further (const std::string_view stem, const std::string_view suffixes, OutputIndexIterator contains_further_it) const
	For each char in suffix appended to stem, check whether this dictionary contains this word and if it may contain longer words with this prefix. More...

Private Member Functions
template<class Func >
auto	run (Func &&func) const

Private Attributes
std::variant< WORDSEARCH_DICTIONARY_CLASSES >	t_

Detailed Description

A type erased wrapper around a particular solver dictionary implementation.

Instances of this should be constructed by SolverDictFactory::make()

Note

Uses std::variant for type erasure internally, so will need to be recompiled if the list of available solver types in the macro WORDSEARCH_DICTIONARY_CLASSES changes.

Member Function Documentation

contains()

bool solver::SolverDictWrapper::contains

(

const std::string_view

word

)

const

Check if this dictionary contains word.

Parameters

[in]

word

The word to check

Returns

true if word is present, else false

contains_further()

template<class OutputIndexIterator >

void solver::SolverDictWrapper::contains_further	(	const std::string_view	stem,
		const std::string_view	suffixes,
		OutputIndexIterator	contains_further_it
	)		const

For each char in suffix appended to stem, check whether this dictionary contains this word and if it may contain longer words with this prefix.

Parameters

[in]	stem
[in]	suffixes
[out]	contains_further_it	This function is what the solver algorithm calls every iteration to ask the dictionary solver implementation to do its work.

contains_further_it should be assigned to and incremented like an output iterator. The value written should be a std::pair<bool, bool>.

Example contains_further implementation:

const auto* node = this->search(stem);
if (!node) {
  return;
}
 
for (const auto [i, c] : ranges::views::enumerate(suffixes)) {
  const std::string_view suffix = {&c, 1};
  const auto contains = detail::contains(*node, suffix);
  const auto further = detail::further(*node, suffix);
  *contains_further_it++ = {contains, further};
}

Each character's position in suffix corresponds to the order that that suffix's output should be written to contains_further_it.

suffixes is not guaranteed to be sorted.

further()

bool solver::SolverDictWrapper::further

(

const std::string_view

word

)

const

Check if this dictionary might contain words with word as a prefix.

Parameters

[in]

word

The prefix to check

Returns

false if there are no more strings in the dictionary with word as a prefix, true if there might be.

Note

Some solvers do not conclusively know whether, for a prefix word, there are more words that contain that prefix. This is acceptable, though sub-optimal and will result in wasted search time, as long as eventually this returns false, assuming for word there are in fact no more words with that prefix.

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

• solver/include/wordsearch_solver/solver/solver.hpp
• solver/include/wordsearch_solver/solver/solver.tpp
• solver/src/solver.cpp