F# has two kinds of data types – “classes” and “types”. Types are bags of bits, similar to C structs, only immutable (that’s C, without sharp). Classes are classes in a normal object-oriented sense.<\/p>\n
F# types cannot be Note, that Confused? I bet you are. And I have one more thing up my sleeve: .NET structs. This is a nut that F# authors did not crack yet.<\/p>\n F# types are .NET structs are both not-nullable, but they are not the same thing. F# types can’t have methods, .NET structs can. F# types don’t derive from Also, while The bottom line is, checking something for F# has two kinds of data types – “classes” and “types”. Types are bags of bits, similar to C structs, only immutable (that’s C, without sharp). Classes are classes in […]<\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"Layout":"","footnotes":""},"categories":[10],"tags":[9],"class_list":["entry","author-ikriv","has-more-link","post-25","post","type-post","status-publish","format-standard","category-fsharp","tag-fsharp"],"_links":{"self":[{"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/25","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=25"}],"version-history":[{"count":0,"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/25\/revisions"}],"wp:attachment":[{"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=25"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=25"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ikriv.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=25"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}null<\/code>. Values that may or may not be present are expressed via special type 'a option<\/code>. So, int option<\/code> means optional integer, conceptually very similar to Nullable<int><\/code>. int option<\/code> can take values None<\/code> or Some(x)<\/code>.
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\nIn Ocaml classes are also not nullable. F# needed to be compatible with .NET libraries, so it introduced null<\/code> keyword, but only for classes. F# classes are both nullable and optionable.<\/p>\nnull<\/code> is not the same as None<\/code>, and Nullable<int><\/code> and int option<\/code> are different data types.<\/p>\nobject<\/code>, .NET structs do. Et cetera, et cetera.<\/p>\nNullable<T><\/code> is conceptually similar to T option<\/code>, these are two different, incompatible things.<\/p>\nnull<\/code> in F# is very not obvious.<\/p>\n","protected":false},"excerpt":{"rendered":"