About

Kapow is a template processor that provides the following directives to support injecting file contents, command output, current date/time, elapsed time, etc in generated output.

It can be used in some different ways:

• Standard: Create a (Markdown) file with Kapow directives then run kapow path/to/file.ext; optionally save the output via redirection: kapow path/to/file.ext >output.ext
• Shebang: Place #!/usr/bin/env kapow as the first line of a (Markdown) file, make it "executable" via chmod +x file.ext, then run via ./file.ext (see note #3 under block directives).

Kapow is designed around Markdown syntax, but can be used with any text format that works with its directives.

Block directives

Notes:

1. Block directives must be placed at the beginning of a line.
2. Long commands can be backslash-wrapped.
3. Included file paths and commands are processed from the directory where the source file is located when it is passed as an argument. However, if the source file is read on stdin or run via shebang, included file paths and commands are processed relative to the current directory. So, if any included files use relative paths or commands that depend on the current directory, it will be necessary to manually change to the source file's directory and then run via ./file.ext.
4. Block directives are entirely replaced by their contents/output, so you are free to embed them inside of or as Markdown syntax... for example, as listing contents, prepend a prompt showing the command, etc.

Span directives

• Span directives must be placed inside a code span and may appear zero or more times in any line.
• Disable processing a span directive by escaping ! with a backslash: \!.

Install

cargo install kapow bat

NOTE: If bat is installed, Kapow uses it for syntax highlighting and paging (see the -p, -P, -H, -l options).

Usage

$ kapow -V
kapow 2.7.0

$ kapow -h
KAPOW!

Usage: kapow [OPTIONS] [PATH]...

Arguments:
  [PATH]...  Source file(s) [default: -]

Options:
  -p             Page output
  -P             Do not page output
  -H             Disable syntax highlighting
  -l <LANG>      Syntax higlight language [default: md]
  -k             Ignore !run directive failures
  -r, --readme   Print readme
  -h, --help     Print help
  -V, --version  Print version

• The -r option uses bat for paging and syntax highlighting if you have it installed (optional).

Errors

NOTE: The kapow process may not appear to have exited with these error codes in "normal usage" because output is piped to bat as a pager if it is installed and output is a TTY and unfortunately bat masks the error code.

Example

See the readme task in Makefile.toml:

• Generates t/VERSION.md from t/VERSION.t.md
  • !run:../target/release/kapow -V
• Generates t/USAGE.md from t/USAGE.t.md
  • !run:../target/release/kapow -h
• Generates README.md from t/README.md
  • !inc:VERSION.md
  • !inc:USAGE.md
  • `!now` (all variants)

Development

cargo install cargo-edit cargo-make cargo-outdated dtg kapow \
miniserve