Hide/shade code not #defined

Gustavo Supplier

Hi,

I would like to know if is there any plugins which is able to do hide/shade code not defined by macros?

In the style of C language, I could not find any option to hide/shaded code not #defined.

If not already implemented, is there any plans to develop such plugin?

Thank you in advance.

PeterJones

@Gustavo-Supplier

How would you expect a text editor to know the difference between.

#define SOMETHING real_name
int SOMETHING = 5;
return SOMETHING;

and

int SOMETHING = 5;
return SOMETHING;

Or any number of combinations where SOMETHING is #defined in a different .h file which is included in the file actively being edited.

How could Notepad++ (or any other text editor) be able to tell you that SOMETHING is undefined in any reliable manner, without being a compiler/linker. (And yes, when Visual Studio tells you there’s something undefined, it’s performing behind-the-scenes compilation/linking or similar… since it’s an IDE bundled with its own compiler/linker, it can do that; Notepad++ is more generic than that, and doesn’t have an associated linker/compiler… especially one that could handle any of the >5 dozen languages that Notepad++ will syntax highlight natively.)

Some of us have ways that we’ve hooked external tools to lint or compiler/error-check code. For example, using the PythonScript plugin, I have defined a callback/notification-handler which will run python2 code through the plugin’s internal python interpreter, or run perl code through my external perl.exe, and report back compiler errors which I display as annotations in Notepad++. This allows me to see errors and know where to fix them.

So that is one possible way of handling it.

Someone could, of course, write a custom plugin to do the same thing – but there aren’t anybody just hanging out in this forum looking for ideas for new plugins, AFAICT, so I’ve never seen a random “can someone write this plugin” request be fulfilled. And if they saw that there was a script in one of the scripting language plugins, unless they were disappointed in the speed/performance/features or they were really interested in the concepts behind it, they wouldn’t likely re-implement in a true plugin.

rdipardo

How could Notepad++ (or any other text editor) be able to tell you that SOMETHING is undefined in any reliable manner, without being a compiler/linker.

In fact, Lexilla’s C/C++ lexer already has a basic implementation of this capability:

lexer.cpp.track.preprocessor Set to 1 to interpret #if/#else/#endif to grey out code that is not active.

https://www.scintilla.org/SciTEDoc.html

Here’s a quick demo in SciTE (where it’s enabled by default; style enhanced for improved visibility):

wscite-inactive-ppd

@Gustavo-Supplier, I think a language server plugin is what you’re looking for.

PeterJones

@rdipardo ,

In fact, Lexilla’s C/C++ lexer already has a basic implementation of this capability:

Cool. I guess it makes sense – I am now thinking it must be only looking at preprocessor directives for the checks, so it’s got an easier job than the example I came up with. When I have some time, I will have to make up a script in PythonScript to enable that attribute, and then play around to confirm where it does and doesn’t come into play.

Gustavo Supplier

@PeterJones thank you for the answer. You sure have broadened my horizons with your explanation. Indeed, I was aiming at a simpler solution as answered by @rdipardo.

PeterJones

@Gustavo-Supplier said in Hide/shade code not #defined:

I was aiming at a simpler solution as answered by @rdipardo.

Since Notepad++ uses Scintilla, then that feature technically exists in Notepad++, but is hidden.

Using the PythonScript plugin and registering a callback, you can make it so that Notepad++ will enable that feature whenever you go into a C/C++ file:

# encoding=utf-8
"""in response to https://community.notepad-plus-plus.org/topic/24173/

Enables the lexer.cpp.track.preprocessor property when it's a C/CPP file;
also needs to set a style for the appropriate StyleID (though I don't know what it is yet)

### === INSTRUCTIONS ===

1. Follow the [FAQ](https://community.notepad-plus-plus.org/topic/23039/faq-desk-how-to-install-and-run-a-script-in-pythonscript) to install PythonScript plugin and this script
2. Run it once normally (per the Usage section of the FAQ)
3. Go to a C/C++ file, and see that code like the following will have different colors for ELSEWHAT and THEREFORE
    ~~~
    #define XYZ
    #ifdef XYZ
    #define ELSEWHAT
    #else
    #define THEREFORE
    #endif
    ~~~
4. If you want this to run every time you run Notepad++,
    1. I assume you named the script PreProcessor24173.py
    2. Put the following lines in your "user startup" script (the FAQ explains how to find that)

            from PreProcessor24173 import PreProcessor24173
            lexer_interface_24173 = PreProcessor24173()


"""
from Npp import editor, notepad, console, NOTIFICATION

class PreProcessor24173(object):
    SCE_C_DEFAULT = 0
    SCE_C_PREPROCESSOR = 9
    SCE_C_PREPROC_HIDDEN = 64 | SCE_C_PREPROCESSOR

    def __init__(self):
        notepad.callback(self.on_bufferactivated, [NOTIFICATION.BUFFERACTIVATED, NOTIFICATION.LANGCHANGED])
        self.on_bufferactivated(None)
        console.write("Registered PreProcessor24173 for C/C++ PREPROCESSOR #define tracking\n")

    def on_bufferactivated(self,args):
        lexer = editor.getLexerLanguage()
        langtype = "{}".format(notepad.getCurrentLang())
        if lexer == 'cpp':
            self.update_cpp()

    def update_cpp(self):
        editor.setProperty("lexer.cpp.track.preprocessor", 1)
        bg = editor.styleGetBack(self.SCE_C_PREPROCESSOR)
        fg = editor.styleGetFore(self.SCE_C_PREPROCESSOR)
        clr = ( (bg[0]+fg[0])//2, (bg[1]+fg[1])//2, (bg[2]+fg[2])//2 ) # halfway between FG and BG
        editor.styleSetFore(self.SCE_C_PREPROC_HIDDEN, clr)

if __name__ == '__main__':
    # notepad.clearCallbacks() # uncomment when debugging
    lexer_interface_24173 = PreProcessor24173()

=== INSTRUCTIONS ===

Follow the FAQ to install PythonScript plugin and this script
Run it once normally (per the Usage section of the FAQ)
Go to a C/C++ file, and see that code like the following will have different colors for ELSEWHAT and THEREFORE
```
#define XYZ
#ifdef XYZ
#define ELSEWHAT
#else
#define THEREFORE
#endif
```
If you want this to run every time you run Notepad++,
1. I assume you named the script PreProcessor24173.py
2. Put the following lines in your “user startup” script (the FAQ explains how to find that)
```
 from PreProcessor24173 import PreProcessor24173
 lexer_interface_24173 = PreProcessor24173()
```

The script chooses the color as halfway between the foreground and background color of the normal #define preprocessor lines – so in light mode (as shown), it will be lighter/faded; in dark mode, it should get darker (so less contrast with the background)

Gustavo Supplier

@PeterJones Thanks for the solution. It helped me a lot.