operator
switch expression (and | &) switch expression or sink expression & sink expression
The & operator is overloaded: it can be used either as a Boolean and operator, or as a tee
operator on sinks.
When applied to arguments of switch type, the & operator is synonymous with the operator and: it returns true if all of its arguments evaluate to true, otherwise the result is false.
When applied to markup sink and string sink expressions, the & operator returns a
string sink. If all arguments are of markup sink type, the result type will be a markup
sink as well. The sink returned by the operator acts as a "tee" connector: any data output into it will be
replicated and distributed to all component sinks that were given as arguments of &.
Usage example:
using output as #error & file "error.log" output "An error occurred."