A string can be extracted from a larger string using the following syntax:
env.getRegexpMatch(stringToMatch, someRegularExpression, occurrence)
This example gets the third occurrence of a sequence of numbers followed by a space, followed by a sequence of letters within string outputLine:
<# value := env.getRegexpMatch(outputLine, "[0-9]+ [a-zA-Z]+", 3) #>
This example gets the interface value from an interface string:
<# interface := env.getRegexpMatch(interface, "[0-9]+/[0-9]+", 1) #>