added REQUIRED to the list of cmake operators and added a regex to capture integers

[DARKMOONlite]

The purpose of this change

To improve readability of CMake code by distinguishing numeric values from other. and adding REQUIRED to the list of parameters that should get some syntactic icing sugar.

I recently was running into issues with a large cmake project and had troubles reading it. After realising that most of my worries came from the fact that I had a deprecated cmake vscode extension that was ruining all syntax highlighting, I decided to try and improve it by submitting what i believe would be a good change to the repo.

Note: I was able to get this working on the main branch as well but since this commit d217cac, effectively removed the advanced syntax highlighting that i was fond of in the latest update I decided to submit the pull request here where they could be combined together to make it very nice to look at. IDK if that was correct, if you want i can submit the pull request from this change

Other Notes/Information

Example:

This was just a sample CMakeLists.txt file, using the Andromeda Italic Bordered theme with the following pull request EliverLara/Andromeda#40 which improves its syntax highlighting for cmake.
this pull request can be effectively replicated by adding the following code to the settings.json file

"editor.tokenColorCustomizations": {
            "[Andromeda Italic Bordered]": {
                "textMateRules": [
                    {
                        "scope": "string.unquoted",
                        "settings": {
                            "foreground": "#D5CED9"
                        }
                    },
                    {
                    "scope": "support.type",
                        "settings": {
                            "foreground": "#c74ded"
                        }
                    }
                ]
            }
        }

As you can see.
Very Mindful. Very Demure.

[hanniavalera]

Hi @DARKMOONlite :) Thanks for the contribution and for caring about CMake readability! 🙂

I have a couple of concerns with the current approach:

REQUIRED as an operator: In CMake's grammar, REQUIRED is a command-specific keyword (e.g., for find_package()), not
a conditional operator like AND/OR/EQUAL that the operators pattern is designed for. See the CMake if() docs (https://cmake.org/cmake/help/latest/command/if.html) for the list of actual condition operators vs. the find_package() docs (https://cmake.org/cmake/help/latest/command/find_package.html) where REQUIRED lives. Mixing them would give REQUIRED the wrong semantic scope (keyword.operator), which could confuse themes and other tooling.

Integer/version highlighting: The regex \bv?\d+(?:.\d+)*\b is quite broad as CMake treats nearly everything as
strings, so this could false-positive on target names, component names, or other identifiers that happen to contain
digits. See CMake language docs on arguments (https://cmake.org/cmake/help/latest/manual/cmake-language.7.html#unquoted-argument) for context on why this is tricky.

I'd suggest narrowing the scope. For example, only highlighting numbers in specific contexts where they're
unambiguously numeric (like version arguments). Happy to discuss further if you'd like to iterate on this! Thanks again :)