1// Package blackfriday is a Markdown processor.
 2//
 3// It translates plain text with simple formatting rules into HTML or LaTeX.
 4//
 5// Sanitized Anchor Names
 6//
 7// Blackfriday includes an algorithm for creating sanitized anchor names
 8// corresponding to a given input text. This algorithm is used to create
 9// anchors for headings when EXTENSION_AUTO_HEADER_IDS is enabled. The
10// algorithm is specified below, so that other packages can create
11// compatible anchor names and links to those anchors.
12//
13// The algorithm iterates over the input text, interpreted as UTF-8,
14// one Unicode code point (rune) at a time. All runes that are letters (category L)
15// or numbers (category N) are considered valid characters. They are mapped to
16// lower case, and included in the output. All other runes are considered
17// invalid characters. Invalid characters that preceed the first valid character,
18// as well as invalid character that follow the last valid character
19// are dropped completely. All other sequences of invalid characters
20// between two valid characters are replaced with a single dash character '-'.
21//
22// SanitizedAnchorName exposes this functionality, and can be used to
23// create compatible links to the anchor names generated by blackfriday.
24// This algorithm is also implemented in a small standalone package at
25// github.com/shurcooL/sanitized_anchor_name. It can be useful for clients
26// that want a small package and don't need full functionality of blackfriday.
27package blackfriday
28
29// NOTE: Keep Sanitized Anchor Name algorithm in sync with package
30//       github.com/shurcooL/sanitized_anchor_name.
31//       Otherwise, users of sanitized_anchor_name will get anchor names
32//       that are incompatible with those generated by blackfriday.