fn:available-environment-variables

Returns a list of environment variable names that are suitable for passing to fn:environment-variable, as a (possibly empty) sequence of strings.

Signature

fn:available-environment-variables() as xs:string*

Properties

This function is deterministic, context-dependent, and focus-independent. It depends on environment variables.

Rules

The function returns a sequence of strings, being the names of the environment variables in the dynamic context in some implementation-dependent order.

The function is deterministic: that is, the set of available environment variables does not vary during evaluation.

Notes

The function returns a list of strings, containing no duplicates.

It is intended that the strings in this list should be suitable for passing to fn:environment-variable.

See also the note on security under the definition of the fn:environment-variable function. If access to environment variables has been disabled, fn:available-environment-variables always returns the empty sequence.