Function parseTag

stackgl_modules/index.js:38971–39021

(tag, TAG_CHR, str, map)

var CHR_sub = '-1'

function parseTag(tag, TAG_CHR, str, map) {

  var opnTag =  "<"  + tag + ">"
  var clsTag =  "</" + tag + ">"

  var nOPN = opnTag.length
  var nCLS = clsTag.length

  var isRecursive = (TAG_CHR[0] === CHR_super0) ||
                    (TAG_CHR[0] === CHR_sub0);

  var a = 0
  var b = -nCLS
  while (a > -1) {
    a = str.indexOf(opnTag, a)
    if(a === -1) break

    b = str.indexOf(clsTag, a + nOPN)
    if(b === -1) break

    if(b <= a) break

    for(var i = a; i < b + nCLS; ++i){
      if((i < a + nOPN) || (i >= b)) {
        map[i] = null
        str = str.substr(0, i) + " " + str.substr(i + 1)
      } else {
        if(map[i] !== null) {
          var pos = map[i].indexOf(TAG_CHR[0])
          if(pos === -1) {
            map[i] += TAG_CHR
          } else { // i.e. to handle multiple sub/super-scripts
            if(isRecursive) {
              // i.e to increase the sub/sup number
              map[i] = map[i].substr(0, pos + 1) + (1 + parseInt(map[i][pos + 1])) + map[i].substr(pos + 2)
            }
          }
        }
      }
    }

    var start = a + nOPN
    var remainingStr = str.substr(start, b - start)

    var c = remainingStr.indexOf(opnTag)
    if(c !== -1) a = c
    else a = b + nCLS
  }

  return map
}

function transformPositions(positions, options, size) {
  var align = options.textAlign || "start"