less-style markdown viewer for UNIX systems

Question

I have a Markdown string in JavaScript, and I\'d like to display it (with bolding, etc) in a less (or, I suppose, more)-style viewer for the comman

Answer 1

I wrote a couple functions based on Keith's answer:

mdt() {
    markdown "$*" | lynx -stdin
}

mdb() {
    local TMPFILE=$(mktemp)
    markdown "$*" > $TMPFILE && ( xdg-open $TMPFILE > /dev/null 2>&1 & )
}

If you're using zsh, just place those two functions in ~/.zshrc and then call them from your terminal like

mdt README.md
mdb README.md

"t" is for "terminal", "b" is for browser.

Answer 2

Pandoc can convert Markdown to groff man pages.

This (thanks to nenopera's comment):

 pandoc -s -f markdown -t man foo.md | man -l -

should do the trick. The -s option tells it to generate proper headers and footers.

There may be other markdown-to-*roff converters out there; Pandoc just happens to be the first one I found.

Another alternative is the markdown command (apt-get install markdown on Debian systems), which converts Markdown to HTML. For example:

markdown README.md | lynx -stdin

(assuming you have the lynx terminal-based web browser).

Or (thanks to Danny's suggestion) you can do something like this:

markdown README.md > README.html && xdg-open README.html

where xdg-open (on some systems) opens the specified file or URL in the preferred application. This will probably open README.html in your preferred GUI web browser (which isn't exactly "less-style", but it might be useful).

Answer 3

I tried to write this in a comment above, but I couldn't format my code block correctly. To write a 'less filter', try, for example, saving the following as ~/.lessfilter:

#!/bin/sh

case "$1" in
    *.md)
        extension-handler "$1"
        pandoc -s -f markdown -t man "$1"|groff -T utf8 -man -
        ;;
    *)
        # We don't handle this format.
        exit 1
esac

# No further processing by lesspipe necessary
exit 0

Then, you can type less FILENAME.md and it will be formatted like a manpage.

Answer 4

If you are into colors then maybe this is worth checking as well:

terminal_markdown_viewer

It can be used straightforward also from within other programs, or python modules.

And it has a lot of styles, like over 200 for markdown and code which can be combined.

Disclaimer

• It is pretty alpha there may be still bugs

• I'm the author of it, maybe some people like it ;-)

Answer 5

A totally different alternative is mad. It is a shell script I've just discovered. It's very easy to install and it does render markdown in a console pretty well.

Answer 6

This is an alias that encapsulates a function:

alias mdless='_mdless() { if [ -n "$1" ] ; then if [ -f "$1" ] ; then cat <(echo ".TH $1 7 `date --iso-8601` Dr.Beco Markdown") <(pandoc -t man $1) | groff -K utf8 -t -T utf8 -man 2>/dev/null | less ; fi ; fi ;}; _mdless '

Explanation

• alias mdless='...' : creates an alias for mdless
• _mdless() {...}; : creates a temporary function to be called afterwards
• _mdless : at the end, call it (the function above)

Inside the function:

• if [ -n "$1" ] ; then : if the first argument is not null then...
• if [ -f "$1" ] ; then : also, if the file exists and is regular then...
• cat arg1 arg2 | groff ... : cat sends this two arguments concatenated to groff; the arguments being:
  • arg1: <(echo ".TH $1 7date --iso-8601Dr.Beco Markdown") : something that starts the file and groff will understand as the header and footer notes. This substitutes the empty header from -s key on pandoc.
  • arg2: <(pandoc -t man $1) : the file itself, filtered by pandoc, outputing the man style of file $1
• | groff -K utf8 -t -T utf8 -man 2>/dev/null : piping the resulting concatenated file to groff:
  • -K utf8 so groff understands the input file code
  • -t so it displays correctly tables in the file
  • -T utf8 so it output in the correct format
  • -man so it uses the MACRO package to outputs the file in man format
  • 2>/dev/null to ignore errors (after all, its a raw file being transformed in man by hand, we don't care the errors as long as we can see the file in a not-so-much-ugly format).
• | less : finally, shows the file paginating it with less (I've tried to avoid this pipe by using groffer instead of groff, but groffer is not as robust as less and some files hangs it or do not show at all. So, let it go through one more pipe, what the heck!

Add it to your ~/.bash_aliases (or alike)