code: function createTerminalFromSerializedGast(prod, topRuleName, dslRuleName) {
          // PATTERN static property will not exist when using custom lexers (hand built or other lexer generators)
          var toolTipTitle = undefined
          // avoid trying to use a custom token pattern as the title.
          if (
              typeof prod.pattern === "string" ||
              Object.prototype.toString.call(prod.pattern) === "[object RegExp]"
          ) {
              toolTipTitle = prod.pattern
          }
  
          return railroad.Terminal(
              prod.label,
              undefined,
              toolTipTitle,
              prod.occurrenceInParent,
              topRuleName,
              dslRuleName,
              prod.name
          )
      }
docs: @param {chevrotain.gast.ISerializedTerminal} prod
  @param {string} topRuleName
  @param {string} dslRuleName
  
  @return {RailRoadDiagram.Terminal}