patch 9.0.1885: Vim9: no support for abstract methods
Problem: Vim9: no support for abstract methods
Solution: Add support for defining abstract methods in an abstract class
closes: #13044
closes: #13046
Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Yegappan Lakshmanan <yegappan@yahoo.com>
diff --git a/runtime/doc/vim9class.txt b/runtime/doc/vim9class.txt
index 8a9e37e..20ad4bb 100644
--- a/runtime/doc/vim9class.txt
+++ b/runtime/doc/vim9class.txt
@@ -358,6 +358,16 @@
An abstract class is defined the same way as a normal class, except that it
does not have any new() method. *E1359*
+ *abstract-method*
+An abstract method can be defined in an abstract class by using the "abstract"
+prefix when defining the function: >
+
+ abstract class Shape
+ abstract def Draw()
+ endclass
+
+A class extending the abstract class must implement all the abstract methods.
+Class methods in an abstract class can also be abstract methods.
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