括弧の対応を表示

paren.sh

showmatch()
{
    parens=''
    expect=''
    str="$1"
    paired=''
    echo "showmatch $str" >&2
    while [ -n "$str" ]
    do
	match=$(expr "$str" : '\([^][}{)(]*[][}{)(]\).*')
	if [ -n "$match" ]; then
	    # strip { }
	    prefix=$(expr "$match" : '\([^][}{)(]*\)[][}{)(]')
	    # get { }
	    paren=$(expr "$match" : '[^][}{)(]*\([][}{)(]\)')
	    remain=$(expr "$str" : '[^][}{)(]*[][}{)(]\(.*\)')

	    case "$paren" in
		'['|'{'|'(')
                    paired="$paired$prefix$paren"
		    parens="$parens$paren"
		    expect=$(pairof "$paren")
		    ;;
		']'|'}'|')')
		    if [ "$expect" = "$paren" ]; then
                        paired="$paired$prefix$paren"
                        parens=$(expr "$parens" : '\(.*\).')
                        expect=$(pairof $(expr "$parens" : '.*\(.\)$'))
                        if [ -z "$parens" ]; then
                            echo "$paired"
                            paired=""
                        fi
                    else
                        echo "unbalanced: $paired$prefix$paren"
                        paired="$paired$prefix$paren"
                    fi
		    ;;
            esac
        else
            break
        fi
        str="$remain"
    done
    if [ -n "$parens" ]; then
        echo "unbalanced: $paired"
    else
        [ -n "$paired" ] && echo "$paired"
    fi
    if [ -n "$str" ]; then
        echo "remain: $str"
    fi
}

pairof()
{
    case "$1" in
        '[') echo ']';;
        '{') echo '}';;
        '(') echo ')';;
        ')') echo '(';;
        '}') echo '{';;
        ')') echo '(';;
    esac
}


str="000{abc[def] [1234] {xyz}}"
showmatch "$str"

str="000{abc[def}} [1234] {xyz}"
showmatch "$str"

str="000{abc{def"
showmatch "$str"

str="000{abc{def}gh{ij{kl{mn}o}}pq{rst}u{v}{w}xy}z"
showmatch "$str"

str="000{abc{def}gh{ij{kl{mn}o}}pq{rst}u{v}{w}xy*z"
showmatch "$str"

str="000{abc{def}gh*ij{kl{mn}o}}pq{rst}u{v}{w}xy}z"
showmatch "$str"

str="000{abc{def}gh*}*ij{kl{mn}o}}pq{rst}u{v}{w}xy}z"
showmatch "$str"

str='\index{\mbox{ABC}\mbox{DEF}{X}\kern.5em{Y}\kern-.2em{Z}}\index{\mbox{GHI}\mbox{JKL}{U}\kern.5em{V}\kern-.2em{W}}'
showmatch "$str"