How to check if an instance is of type String or GString in Groovy

Question

I would like to learn what the robust way of checking, if a variable is of type string or gstring, is. I suppose it is different than in pure Java:

def var =         


        

Answer 1

Another way is to use the in keyword:

groovy:000> t = "hello"
===> hello
groovy:000> t in String
===> true
groovy:000> "${t}" in GString
===> true

The in keyword is the membership operator, and gets translated to an isCase call on the class:

groovy:000> String.isCase(t)
===> true
groovy:000> GString.isCase("${t}")
===> true