BAT
A cat(1) clone with syntax highlighting and Git integration
..., you can still use bat to concatenate files. Whenever bat detects a non-interactive terminal (i.e. when you pipe into another process or into a file), bat will act as a drop-in replacement for cat and fall back to printing the plain file contents, regardless of the --pager option's value. Use bat --list-themes to get a list of all available themes for syntax highlighting.