[boost] spirit: Using actions on rules with more precision

Hello, Is it possible to define a rule: rule<> mystringrule = confix_p('"', *c_escape_ch_p, '"') differently such that I can use std::string value; bool result = parse("\"hello world\"", mystringrule[assign_a(value)]).full; and get the text = "hello world" assigned to value? Currently, I get text = "\"hello world\"" instead. ie with double quotes at either end. Thanks -John