{"id":3869,"date":"2021-10-19T12:13:33","date_gmt":"2021-10-19T12:13:33","guid":{"rendered":"http:\/\/www.istratech.hr\/?p=3869"},"modified":"2022-09-30T10:38:43","modified_gmt":"2022-09-30T10:38:43","slug":"do-cows-eat-grass","status":"publish","type":"post","link":"https:\/\/www.istratech.hr\/en\/do-cows-eat-grass\/","title":{"rendered":"Do cows eat grass?"},"content":{"rendered":"<p style=\"text-align:center;\"><strong>ABSTRACT<\/strong><\/p>\n\n\n<p class=\"wp-block-paragraph\"> In the example, covariance is attempted to be applied to two related superclass\/subclass pairs. In this particular case these are the classes Animal\/Cow and Animal_food\/Cow_food. <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">In one procedure of the Animal class there is a parameter of the Animal_food class. Can we (in the languages listed above) in the Cow subclass make an overridden procedure that uses the Cow_food class instead of the Animal_food class? One language had this feature from the beginning (late 80&#8217;s), but this feature allowed a runtime error, which was resolved in 2014. But there is another language (among the languages listed above) that makes this possible, in a different way. <\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><em>Note: the use of generic parameters (and their covariance) is not the &#8220;right&#8221; solution (it is a solution, but with major practical drawbacks). <\/em><\/p>\n\n\n<div class=\"more\"><a href=\"http:\/\/www.istratech.hr\/wp-content\/uploads\/2021\/10\/HROUG2021_Sirotic_2.pdf\" target=\"_blank\" rel=\"noopener noreferrer\">VIEW LECTURE<\/a><\/div>","protected":false},"excerpt":{"rendered":"<p>The topic is the covariance of non-generic parameters in the languages PL\/SQL, C ++, Eiffel, Java, Scala, Kotlin (except PL\/SQL, the order of other languages is the order of their occurrence).<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_exactmetrics_skip_tracking":false,"_uf_show_specific_survey":0,"_uf_disable_surveys":false,"_themeisle_gutenberg_block_has_review":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[172,330,327],"tags":[],"class_list":["post-3869","post","type-post","status-publish","format-standard","hentry","category-blog-en","category-conferences","category-hroug-en"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v28.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>Do cows eat grass? 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