qbonnard/jekyll — comment on commit 6857e817866bf66cfd3ced1ced79e0b8a7cf30da
File: lib/jekyll/tags/extract.rb line 43
By crohr:

Use `String#each_line` or `String#index` to find matching lines.
Ex:

first_line_index = source.index(@before)
last_line_index = source.index(@after, first_line_index)
if first_line_index && last_line_index
Liquid...
else
"Unable to..."
end