page_number.go

package main

import(
  "regexp"
)

var(
	pageRe         *regexp.Regexp = regexp.MustCompile(`\bp.\s*(\d+)\b`)
	pagesRe        *regexp.Regexp = regexp.MustCompile(`\bpp.\s*(\d+)-(\d+)\b`)
)

func linkPageNumbers(input string, pdfUrl string) string {
	link := fmt.Sprintf("[${0}](%s#page=${1})", pdfUrl)
	return pagesRe.ReplaceAllString(
		pageRe.ReplaceAllString(input, link),
		link,
	)
}