runtime(doc): Update the 'specifies' keyword documentation, slightly reformat
Commit: https://github.com/vim/vim/commit/44831e4beaa8340ee2e3cc51c9c8882784b0d142 Author: Yegappan Lakshmanan <yegap...@yahoo.com> Date: Sun Feb 16 16:15:50 2025 +0100 runtime(doc): Update the 'specifies' keyword documentation, slightly reformat closes: https://github.com/vim/vim/issues/16648 Signed-off-by: Yegappan Lakshmanan <yegap...@yahoo.com> Signed-off-by: Christian Brabandt <c...@256bit.org> diff --git a/runtime/doc/vim9class.txt b/runtime/doc/vim9class.txt index 5e5c28e9e..7ba91e7d9 100644 --- a/runtime/doc/vim9class.txt +++ b/runtime/doc/vim9class.txt @@ -1,4 +1,4 @@ -*vim9class.txt* For Vim version 9.1. Last change: 2025 Feb 11 +*vim9class.txt* For Vim version 9.1. Last change: 2025 Feb 16 VIM REFERENCE MANUAL by Bram Moolenaar @@ -52,7 +52,6 @@ An interface is used to specify properties of an object: The class hierarchy allows for single inheritance. Otherwise interfaces are to be used where needed. - Class modeling ~ You can model classes any way you like. Keep in mind what you are building, @@ -122,7 +121,6 @@ using the object name followed by a dot following by the member: > A class name cannot be used as an expression. A class name cannot be used in the left-hand-side of an assignment. - Object variable write access ~ *read-only-variable* Now try to change an object variable directly: > @@ -626,13 +624,15 @@ once. They can appear in any order, although this order is recommended: > extends ClassName implements InterfaceName, OtherInterface specifies SomeInterface -< *E1355* *E1369* +< +The "specifies" feature is currently not implemented. + + *E1355* *E1369* Each variable and method name can be used only once. It is not possible to define a method with the same name and different type of arguments. It is not possible to use a public and protected member variable with the same name. An object variable name used in a super class cannot be reused in a child class. - Object Variable Initialization ~ If the type of a variable is not explicitly specified in a class, then it is @@ -689,13 +689,12 @@ A class can implement one or more interfaces. The "implements" keyword can only appear once *E1350* . Multiple interfaces can be specified, separated by commas. Each interface name can appear only once. *E1351* - A class defining an interface ~ *specifies* A class can declare its interface, the object variables and methods, with a named interface. This avoids the need for separately specifying the interface, which is often done in many languages, especially Java. - +TODO: This is currently not implemented. Items in a class ~ *E1318* *E1325* *E1388* @@ -736,25 +735,25 @@ Some of the builtin functions like |empty()|, |len()| and |string()| can be used with an object. An object can implement a method with the same name as these builtin functions to return an object-specific value. - *E1412* + *E1412* The following builtin methods are supported: - *object-empty()* + *object-empty()* empty() Invoked by the |empty()| function to check whether an object is empty. If this method is missing, then true is returned. This method should not accept any arguments and must return a boolean. - *object-len()* + *object-len()* len() Invoked by the |len()| function to return the length of an object. If this method is missing in the class, then an error is given and zero is returned. This method should not accept any arguments and must return a number. - *object-string()* + *object-string()* string() Invoked by the |string()| function to get a textual representation of an object. Also used by the |:echo| command for an object. If this method is missing in the class, then a built-in default textual representation is used. This method should not accept any arguments and must return a string. - *E1413* + *E1413* A class method cannot be used as a builtin method. Defining an interface ~ @@ -786,7 +785,6 @@ An interface can only be defined in a |Vim9| script file. *E1342* An interface cannot "implement" another interface but it can "extend" another interface. *E1381* - null object ~ When a variable is declared to have the type of an object, but it is not @@ -795,7 +793,6 @@ does not know what class was supposed to be used. Vim then cannot check if a variable name is correct and you will get a "Using a null object" error, even when the variable name is invalid. *E1360* *E1362* - Default constructor ~ *default-constructor* In case you define a class without a new() method, one will be automatically @@ -1118,7 +1115,6 @@ For |Vim9| script using the same method name for all constructors seemed like the right choice, and by calling it new() the relation between the caller and the method being called is obvious. - No overloading of the constructor ~ In Vim script, both legacy and |Vim9| script, there is no overloading of @@ -1139,7 +1135,6 @@ That way multiple constructors with different arguments are possible, while it is very easy to see which constructor is being used. And the type of arguments can be properly checked. - No overloading of methods ~ Same reasoning as for the constructor: It is often not obvious what type @@ -1148,7 +1143,6 @@ actually being called. Better just give the methods a different name, then type checking will make sure it works as you intended. This rules out polymorphism, which we don't really need anyway. - Single inheritance and interfaces ~ Some languages support multiple inheritance. Although that can be useful in @@ -1164,7 +1158,6 @@ it will be checked if that change was also changed. The mechanism to assume a class implements an interface just because the methods happen to match is brittle and leads to obscure problems, let's not do that. - Using "this.variable" everywhere ~ The object variables in various programming languages can often be accessed in @@ -1183,7 +1176,6 @@ variables. Simple and consistent. When looking at the code inside a class it's also directly clear which variable references are object variables and which aren't. - Using class variables ~ Using "static variable" to declare a class variable is very common, nothing @@ -1197,7 +1189,6 @@ the class. This has two problems: The class name can be rather long, taking up quite a bit of space, and when the class is renamed all these places need to be changed too. - Declaring object and class variables ~ The main choice is whether to use "var" as with variable declarations. @@ -1251,7 +1242,6 @@ function declaration syntax for class/object variables and methods. Vim9 also reuses the general function declaration syntax for methods. So, for the sake of consistency, we require "var" in these declarations. - Using "ClassName.new()" to construct an object ~ Many languages use the "new" operator to create an object, which is actually @@ -1315,7 +1305,6 @@ An alternative would have been using the "protected" keyword, just like "public" changes the access in the other direction. Well, that's just to reduce the number of keywords. - No private object variables ~ Some languages provide several ways to control access to object variables. -- -- You received this message from the "vim_dev" maillist. 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