#!/usr/bin/env bash

# Finds all tags referenced in one post.
# Accepts either filename as first argument, or post content at stdin
# Prints one line with space-separated tags to stdout
declare template_tags_line_header
tags_in_post() {
    sed -n "/^<p>$template_tags_line_header/{s/^<p>$template_tags_line_header//;s/<[^>]*>//g;s/[ ,]\+/ /g;p;}" "$1" | tr ', ' ' '
}