How to create a simple custom language colorization to VS Code

Question

I\'m trying to create a simple colorization for log files, now that it\'s possible include custom languages in Code (I\'m on 0.9.2). I have created a simple .tmLanguage file

Answer 1

You need to use regular expressions instead of static strings to describe the pattern:

match
q  <- This needs to be a regular expression
name
comment

I provide a more useful example for a log file highlighter. It colors numbers, hints, warnings and errors in different colors. The rules to identify these keywords and numbers are based on regular expression.

    
        scopeName
        text.log

        fileTypes
        
            log
        

        name
        Log file

        patterns
        
            
                match
                \b(?i:(hint|info|information))\b
                name

                info-token
                            
            
                match
                \b(?i:(warning|warn))\b
                name
                warn-token
            
            
                match
                \b(?i:(Error|Failure|Fail))\b
                name
                error-token
            
            
                match
                \b((0(x|X)[0-9a-fA-F]*)|(([0-9]+\.?[0-9]*)|(\.[0-9]+))((e|E)(\+|-)?[0-9]+)?)(L|l|UL|ul|u|U|F|f|ll|LL|ull|ULL)?\b
                name
                constant.numeric
                                            
        
        uuid
        FF0550E0-3A29-11E3-AA6E-0800200C9A77
    

The highlighter gives a result like this (using the default theme):

I didn't find an official documentation about the available tokens (like error-token, constant.numeric etc). But there is a file located in %VSCODE_INSTALLATION%\resources\app\out\vs\languages\markdown\common\tokens.css. It seems to list all available tokens etc. Use it as a reference when you create the .tmLanguage file.

But pay attention: Some themes are using only the basic tokens. And some other themes are using the same color for many different tokens. So you should test the highlighter frequently against the most common themes to see whether the result looks good or not.

You should definitely visit this page about Language Grammars to learn more.