int isSet($var1[, $var2...])

•$varx - the names of the variables to check to see if they are all set (that they all have a value)

•Returns nonzero if all listed variables have been set (and thus have a value assigned)

•Returns 0 if any listed variable is not assigned a value

•Example: to see if $varname is defined, use isSet($varname), DO NOT use isSet('varname')

•It is recommended that this function be used instead of isDefined().

•This function is supported only in CSE HTML Validator v11.9910 and later.