fix highlighted markdown files in Vim

• syntax files loading procedurce
  • 1 $VIM/vimfiles/syntax/type.vim (~/.vim/syntax/type.vim)
  • 2 $VIMRUNTIME/syntax/type.vim
  • 3 $VIM/vimfiles/after/syntax/type.vim (~/.vim/after/syntax/type.vim)

create markdown.vim in after/syntax

• priority When several syntax items may match, these rules are used:
  • 1 When multiple Match or Region items start in the same position, the item defined last has priority.
  • 2 A Keyword has priority over Match and Region items.
  • 3 An item that starts in an earlier position has priority over items that start in later positions.

syn region markdownItalic start="\S\@<=\*\|\*\S\@=" end="" keepend contains=markdownLineStart
syn region markdownItalic start="\S\@<=_\|_\S\@=" end="" keepend contains=markdownLineStart

in markdown.vim, add two lines above.