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<p class="MsoNormal"><span lang="PT">Greetings;<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="PT"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="PT">This email's purpose is to request comments from this mailing list regarding a PR to ‘unordered-containers’ (here:
<a href="https://github.com/tibbe/unordered-containers/pull/170">https://github.com/tibbe/unordered-containers/pull/170</a>).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="PT"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="PT">This PR modifies the existing code so that ‘size’ can calculate the size of a ‘Hash{Map, Set}’ in constant time instead of linear, which is its current performance.</span><span lang="EN-US"><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">To avoid making this message too large, the benchmarking results are not included here, but you may find them in the PR’s discussion. In short, a penalty of about 10% to functions in the library may be expected, and both
‘filterWithKey’ and ‘fromListWith’ are much slower, which is an issue I’d like to solve.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">If this PR is mediocre, if you have any suggestions to make it better, or any other comment, please reply to this email.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-US">I'd like to thank David Feuer and Niklas Hambüchen for the many improvements suggested to this PR, and Johan Tibell for writing an excellent library.</span></p>
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