code: function registerTaggedDual(numberTag, numericTag, checkFn, toJSONSchema) {
  		context.registerTaggedType({
  			tag: numberTag,
  			jsonType: 'number',
  			minArgs: 2,
  			maxArgs: 2,
  			sparse: true,
  			numeric: true
  		}, checkFn, returnOriginal, toJSONSchema)
  
  		context.registerTaggedType({
  			tag: numericTag,
  			jsonType: 'string',
  			minArgs: 2,
  			maxArgs: 2,
  			sparse: true,
  			numeric: true
  		}, (value, args) => {
  			let numberValue = toNumber(value)
  			checkFn(numberValue, args)
  			return numberValue
  		}, returnOriginal, extra => ({
  				type: 'string',
  				format: extra.original
  			}))
  	}
docs: Register number and numeric dual tagged types
  @param {string} numberTag
  @param {string} numericTag
  @param {Function} checkFn
  @param {function(*):Object} toJSONSchema
  @private