I´m having to many problems with the second eval().
I created a new field and a button with rules (to can see what´s doing Infopath when I press the button):
First Rule: Any conditions and Action "Set Value of a Field" (It´s correct?? I use the Spanish version and I don´t know the English name) and I choice my new field and Xpath: concat(DisplayName; ";")
Second Rule: If "new field" doesnt empty, Action ¿"Display value of a Field"? and Xpath: eval("new field"; concat(....))
Third Rule: If "new field" doesnt empty, Action ¿"Display value of a Field"? and Xpath: eval(eval("new field"; concat());"..")
And the problem is in the third rule. There is a problem with the function eval().
I´m sorry but I´m a Mechanical Engineer and my knowlegdes about Xpath and computer programming are very limited.