foreach with the same variable but with interactions

[Ariel Soto-Caro]

Hello,
I'm trying to iterate over a regression changing a single variable for its self-interactions like this:

foreach var of varlist c.myVar  c.myVar#c.myVar c.myVar##c.myVar  c.myVar#c.myVar#c.myVar c.myVar##c.myVar##c.myVar {
reg y $controls `var', r
}

But I get an error message:

c:  operator invalid

I need the c operator in order to set the interactions. I think this would be very straightforward for an experienced Stata person.
Can anybody give me an idea on how to address this?
Thank you so much in advance.

[Clyde Schechter]

The problem is that when you include the c., #, and ## operators, what you have is no longer the name of a variable, and only variable names can appear in a varlist. Try this instead:

foreach var in c.myVar c.myVar#c.myVar c.myVar##c.myVar c.myVar#c.myVar#c.myVar c.myVar##c.myVar##c.myVar {
    reg y $controls `var', r
}

[Ariel Soto-Caro]

The problem is that when you include the c., #, and ## operators, what you have is no longer the name of a variable, and only variable names can appear in a varlist. Try this instead:

foreach var in c.myVar c.myVar#c.myVar c.myVar##c.myVar c.myVar#c.myVar#c.myVar c.myVar##c.myVar##c.myVar {
reg y $controls `var', r
}

It worked perfectly. Thank you so much!