All posts by Dominik

Dominik is a PhD student at the Control Theory and Robotics Lab, TU Darmstadt, as part of the Research Training Group GKMM (GRK1362). My research focuses on state estimation in distributed systems. As hobby, I contribute to the KDE project and work on the Kate application and editor component.

Improving Syntax Highlighting Files

When building the KSyntaxHighlighting framework, the syntax highlighting xml files are compiled into the KSyntaxHighlighting library. In order to do so, we have a small little helper program that generates an index of all xml files. This indexer also validates the xml files against the XML Schema, and performs some more sanity checks.

Review request D10621 tries to extend the indexer even further and suggest optimizations for our highlighting files. For instance, the rule

 <AnyChar context="#stay" String="&space;" attribute="Normal Text" />

should be replaced by the faster rule

 <DetectChar context="#stay" char="&space;" attribute="Normal Text" />

Similarly, the rule

 <RegExpr attribute="Normal" context="conditionNot" String="\bnot\b" lookAhead="true" insensitive="true"/>

should be replaced by the much faster rule

 <WordDetect attribute="Normal" context="conditionNot" String="not" lookAhead="true" insensitive="true"/>

The proposed patch above generates more than 1500 suggestions to improve our highlighting files, so a lot of work. Help would be very much appreciated. So if you would like to contribute to KDE and are looking for simple work to do, then feel free to get started by sending improved highlighting files to us via phabricator.kde.org (click “Code Review” on the left, and then “Create Diff” on the top right – or even better use arc to automatically manage your patches). Oh, and please increase the version number in the xml files whenever you provide a patch 🙂

Fancy Terminal Prompt

By default, the terminal looks as follows on my Linux distribution:

However, if you are working a lot on the terminal, there are a lot of scripts and tricks available in the net that improve the information displayed in the terminal in many ways. For instance, since many many years, I have the following at the end of my ~/.bashrc:

# use a fancy prompt
PS1="\[\033[01;32m\]\u@\h\[\033[00m\]:\[\033[01;34m\]\W\[\033[00m\]"
PS1="$PS1 \`if [ \$? = 0 ]; then echo -e '\[\033[01;32m\]:-)';"
PS1="$PS1 else echo -e '\[\033[01;31m\]:-(' \$?; fi\`\[\033[00m\]"
PS1="$PS1 \$(__git_ps1 \"(%s)\") \$ "

Once you open a new terminal, then the appearance is as follows:

As you can see, now I have nice colors: The hostname is green, the folder is blue, the return value of the last executed command is a green 🙂 in case of success (exit code = 0), and a red 🙁 in case of errors (exit code != 0). In addition, the last part shows the current git branch (master). Showing the git branch is very useful especially if you are using arc a lot and work with many branches.

I am sure there are many more cool additions to the terminal. If you have some nice additions, please share – maybe also as a new blog?