Extract the content from inside an HTML tag with sed and a regex

example <title>this is it</title> if we want to extract just this is it.

echo '<title>this is it</title>' | sed -nE 's/<title>(.*)<\/title>/\1/p'

Regex Find and select HTML attributes - such as a "class" name, even if it spans multiple lines.

(class=".*?")

Add a whitespace character to pad all content within brackets

I had to use this to do a global find/replace all within many files to reformat things like:

{{this}}

to

{{ this }}

Using gnu-sed instead of OS X sed because of compatability issues using -i with Mac version of sed. (brew install gnu-sed)

find . -type f -name '*.njk' | while read file; 
do 
  gsed -i 's/{{\(\S\)/{{ \1/g' $file; 
  gsed -i 's/\(\S\)}}/\1 }}/g' $file; 
done