bat-cat

This skill provides guidance for using a modern replacement for the standard file printing utility, adding syntax highlighting, line numbers, version control change markers, and paging. It documents viewing modes, language detection and forcing, theme selection, line ranges, decorations, and non-printable character display. The dependency is a compiled binary installed through a package manager, so it is not available by default on minimal systems. There is also a practical caveat: the decorated output includes line numbers and headers, which is exactly wrong when text is piped into another program or compared byte for byte, so the plain mode flag must be used deliberately.

Use case: reviewing a source file with local changes visible

Bat is a drop in replacement for cat that adds syntax highlighting, line numbers and git change markers, which makes it useful for reading code and configuration out loud rather than scrolling through a pager. Its defaults are intentionally richer than cat, so most invocations need a flag or two to look plain again. ## What it does - Detects the language from the file extension and highlights it with no configuration at all. - Prints line numbers by default, and a plain mode strips both the numbers and the file header. - Accepts explicit line ranges such as a start and end pair, so one region of a long file can be read alone. - Marks added, removed and modified lines when the file sits inside a git repository. - Squeezes repeated blank lines and can show non printable characters on request. ## When it is the wrong choice It only helps when the bat binary is installed, because nothing here falls back to a plain cat. It is also a viewer rather than an editor, so it cannot change anything about what it prints. The git markers are decoration that appears only for tracked files, which means a repository free workflow gets none of that value. The plain and squeeze flags exist precisely because the rich default output is wrong for machine consumption, so anything that parses output expecting a bare stream needs those flags set explicitly rather than assuming the default is safe. ```bash bat -p script.sh bat -r 10:20 notes.txt bat -l javascript config.txt ``` ## Working notes - Plain mode is the closest thing to cat and is the safest default inside scripts. - The forced language flag matters for configuration files that have no extension. - Theming is set once in a configuration file rather than repeated on every call.