runtime(java): Optionally highlight parameterised types
In the presence of parameterised types whose names begin
with a capital letter and end with a less-than sign "<" that
introduces a type argument or a list of comma-separated type
arguments, followed by a greater-than sign ">", a variable
"g:java_highlight_generics" can be defined to have some
components of such types uniformly coloured (by picking
highlight groups for javaGenericsC{1,2}, javaWildcardBound).
For example,
------------------------------------------------------------
java.io.InputStream stream = java.io.InputStream.nullInputStream();
java.util.function.Function<String,
java.util.function.BiFunction<String, String, String>> updater =
property -> (oldValue, newValue) -> oldValue;
java.util.logging.LogManager.getLogManager()
.updateConfiguration(stream, updater);
------------------------------------------------------------
Note that the diamond form and explicit type arguments do
not qualify for this kind of recognition.
For example,
------------------------------------------------------------
new java.util.HashSet<>().<String>toArray(new String[0]);
------------------------------------------------------------
References:
https://docs.oracle.com/javase/specs/jls/se21/html/jls-4.html#jls-4.5
https://docs.oracle.com/javase/specs/jls/se21/html/jls-15.html#jls-15.9
https://docs.oracle.com/javase/specs/jls/se21/html/jls-15.html#jls-15.12.2.1
closes: #15050
Signed-off-by: Aliaksei Budavei <0x000c70@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/doc/syntax.txt b/runtime/doc/syntax.txt
index c07c3a4..1460edd 100644
--- a/runtime/doc/syntax.txt
+++ b/runtime/doc/syntax.txt
@@ -1,4 +1,4 @@
-*syntax.txt* For Vim version 9.1. Last change: 2024 Jun 17
+*syntax.txt* For Vim version 9.1. Last change: 2024 Jun 19
VIM REFERENCE MANUAL by Bram Moolenaar
@@ -2014,7 +2014,7 @@
Function names are not highlighted, as the way to find functions depends on
how you write Java code. The syntax file knows two possible ways to highlight
-functions:
+headers of function declarations:
If you write function declarations that are consistently indented by either
a tab, or a space . . . or eight space character(s), you may want to set >
@@ -2032,10 +2032,14 @@
supposed to be named (with respect to upper- and lowercase) and there is any
amount of indentation, you may want to set >
:let java_highlight_functions="style"
-If neither setting does work for you, but you would still want function
-declarations to be highlighted, create your own definitions by changing the
-definitions in java.vim or by creating your own java.vim that includes the
-original one and then adds the code to highlight functions.
+If neither setting does work for you, but you would still want headers of
+function declarations to be highlighted, modify the current syntax definitions
+or compose new ones.
+
+Higher-order function types can be hard to parse by eye, so uniformly toning
+down some of their components may be of value. Provided that such type names
+conform to the Java naming guidelines, you may arrange it with >
+ :let java_highlight_generics=1
In Java 1.1 the functions System.out.println() and System.err.println() should
only be used for debugging. Therefore it is possible to highlight debugging