Сопоставление с образцом (pattern matching) — сильный механизм языков программирования, который, к сожалению, встречается не так часто. Причём, как в коде разработчиков, так и в поддержке со стороны самого языка.
Разработчики на функциональных языках используют этот механизм довольно часто, потому что у них вообще многое определяется статически через правильный подход к системе типов. Разработчики же на императивных языках очень любят огромные многоуровневые ветвления. Есть даже такое понятие «Спагетти-код» — раньше его применяли к коду, перегруженному операторами перехода, но в современном виде это скорее об избытке операторов условия.
Pattern matching позволяет накладывать на объекты некоторый трафарет и смотреть, попадают ли они под него. Это не только выглядит лаконичнее и короче, чем дерево условий, но ещё и понятнее с точки зрения восприятия человеком: вот у нас заказ содержит более 10 элементов и при этом стоит более 1000 долларов, значит делаем на него скидку 10 центов. При этом трафарет работает как сортировщик монеток: самая маленькая проваливается в первый паз, следующая по размеру в следующий итд, применение условий идёт сверху вниз. Есть и неявный плюс: такой подход автоматически провоцирует разработчиков проводить проверку на null. Ведь null не может подходить под трафарет «содержит более 10 товаров».
К счастью, в C# этот механизм в последних версиях активно развивают и совершенствуют. И это одно из многочисленных преимуществ C# над Java.
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Our #LassaFever situation report for week 1, 2025 has been published.
54 cases have been confirmed and 10 deaths have been recorded across 6 states in Nigeria.
🔗Download, read, and share via https://ncdc.gov.ng/ncdc.gov.ng/themes/common/files/sitreps/1bded1685f8dc4961a169a274be138c2.pdf
Our #LassaFever situation reports for weeks 42, 2024 have been published.
The weekly report provides a summary of the #LassaFever epidemiological situation and response activities in Nigeria.
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https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our #LassaFever situation report for week 40, 2024 has been published.
1025 cases have been confirmed and 174 deaths have been recorded across 28 states in Nigeria.
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https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our latest #LassaFever situation report shows that 982 confirmed cases and 168 deaths have been recorded in 2024.
This loss of lives is not just a number but a significant loss of a family member, friend, colleague or a seasoned healthcare worker
CEPI vaccines writes on the critical need for a #LassaFever vaccine to control this disease.
🔗
https://cepi.net/lassa-vaccine-urgently-needed-save-thousands-lives
Situation report: https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
We have published our latest #LassaFever epidemiology data.
Here you can find a summary of all the latest figures in our weekly infographic.🔽
The full report can be accessed via
🔗https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our #LassaFever situation report for week 32, 2024 has been published.
The weekly report provides a summary of the #LassaFever epidemiological situation and response activities in Nigeria.
🔗Download, read, and share via
https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our #LassaFever situation report for week 30, 2024 has been published.
The weekly report provides a summary of the #LassaFever epidemiological situation and response activities in Nigeria.
🔗Download, read, and share via
https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our #LassaFever situation reports for weeks 28 and 29, 2024 have been published.
The weekly report provides a summary of the #LassaFever epidemiological situation and response activities in Nigeria.
🔗Download, read, and share via
https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our #LassaFever situation report for week 25, 2024 has been published.
The weekly report provides a summary of the #LassaFever epidemiological situation and response activities in Nigeria.
🔗Download, read, and share via
https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our #LassaFever situation report for week 24, 2024 has been published.
The weekly report provides a summary of the #LassaFever epidemiological situation and response activities in Nigeria.
🔗Download, read, and share via
https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our #LassaFever situation report for week 23, 2024 has been published.
The weekly report provides a summary of the #LassaFever epidemiological situation and response activities in Nigeria.
🔗Download, read, and share via
https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria
Our #LassaFever situation report for week 21, 2024 has been published.
The weekly report provides a summary of the #LassaFever epidemiological situation and response activities in Nigeria.
🔗Download, read, and share via
https://ncdc.gov.ng/diseases/sitreps/?cat=5&name=An%20update%20of%20Lassa%20fever%20outbreak%20in%20Nigeria