You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
67 lines
2.6 KiB
Go
67 lines
2.6 KiB
Go
// Package stripmd strips Markdown from text
|
|
package stripmd
|
|
|
|
import (
|
|
"regexp"
|
|
)
|
|
|
|
var (
|
|
listLeadersReg = regexp.MustCompile(`(?m)^([\s\t]*)([\*\-\+]|\d\.)\s+`)
|
|
|
|
headerReg = regexp.MustCompile(`\n={2,}`)
|
|
strikeReg = regexp.MustCompile(`~~`)
|
|
codeReg = regexp.MustCompile("`{3}" + `.*\n`)
|
|
|
|
htmlReg = regexp.MustCompile("<(.*?)>")
|
|
emphReg = regexp.MustCompile(`\*\*([^*]+)\*\*`)
|
|
emphReg2 = regexp.MustCompile(`\*([^*]+)\*`)
|
|
emphReg3 = regexp.MustCompile(`__([^_]+)__`)
|
|
emphReg4 = regexp.MustCompile(`_([^_]+)_`)
|
|
setextHeaderReg = regexp.MustCompile(`^[=\-]{2,}\s*$`)
|
|
footnotesReg = regexp.MustCompile(`\[\^.+?\](\: .*?$)?`)
|
|
footnotes2Reg = regexp.MustCompile(`\s{0,2}\[.*?\]: .*?$`)
|
|
imagesReg = regexp.MustCompile(`\!\[(.*?)\]\s?[\[\(].*?[\]\)]`)
|
|
linksReg = regexp.MustCompile(`\[(.*?)\][\[\(].*?[\]\)]`)
|
|
blockquoteReg = regexp.MustCompile(`>\s*`)
|
|
refLinkReg = regexp.MustCompile(`^\s{1,2}\[(.*?)\]: (\S+)( ".*?")?\s*$`)
|
|
atxHeaderReg = regexp.MustCompile(`(?m)^\#{1,6}\s*([^#]+)\s*(\#{1,6})?$`)
|
|
atxHeaderReg2 = regexp.MustCompile(`([\*_]{1,3})(\S.*?\S)?P1`)
|
|
atxHeaderReg3 = regexp.MustCompile("(?m)(`{3,})" + `(.*?)?P1`)
|
|
atxHeaderReg4 = regexp.MustCompile(`^-{3,}\s*$`)
|
|
atxHeaderReg5 = regexp.MustCompile("`(.+?)`")
|
|
atxHeaderReg6 = regexp.MustCompile(`\n{2,}`)
|
|
)
|
|
|
|
// Strip returns the given string sans any Markdown.
|
|
// Where necessary, elements are replaced with their best textual forms, so
|
|
// for example, hyperlinks are stripped of their URL and become only the link
|
|
// text, and images lose their URL and become only the alt text.
|
|
func Strip(s string) string {
|
|
res := s
|
|
res = listLeadersReg.ReplaceAllString(res, "$1")
|
|
|
|
res = headerReg.ReplaceAllString(res, "\n")
|
|
res = strikeReg.ReplaceAllString(res, "")
|
|
res = codeReg.ReplaceAllString(res, "")
|
|
|
|
res = emphReg.ReplaceAllString(res, "$1")
|
|
res = emphReg2.ReplaceAllString(res, "$1")
|
|
res = emphReg3.ReplaceAllString(res, "$1")
|
|
res = emphReg4.ReplaceAllString(res, "$1")
|
|
res = htmlReg.ReplaceAllString(res, "$1")
|
|
res = setextHeaderReg.ReplaceAllString(res, "")
|
|
res = footnotesReg.ReplaceAllString(res, "")
|
|
res = footnotes2Reg.ReplaceAllString(res, "")
|
|
res = imagesReg.ReplaceAllString(res, "$1")
|
|
res = linksReg.ReplaceAllString(res, "$1")
|
|
res = blockquoteReg.ReplaceAllString(res, " ")
|
|
res = refLinkReg.ReplaceAllString(res, "")
|
|
res = atxHeaderReg.ReplaceAllString(res, "$1")
|
|
res = atxHeaderReg2.ReplaceAllString(res, "$2")
|
|
res = atxHeaderReg3.ReplaceAllString(res, "$2")
|
|
res = atxHeaderReg4.ReplaceAllString(res, "")
|
|
res = atxHeaderReg5.ReplaceAllString(res, "$1")
|
|
res = atxHeaderReg6.ReplaceAllString(res, "\n\n")
|
|
return res
|
|
}
|