Expect - Expecting while interacting - expect

Question

I want to "listen" for a string outputted by the shell, while being in "interact" mode. Or i want to emulate interact mode somehow, that still allows me to listen for a specific string from the shell.
It seems interact only listens to the users input (the keys I press) and not what is returned by the shell.
How would I go about having Expect executing something everytime it sees a specific string, but otherwise let me use the shell interactively an unhindered?.
Example:
proc yay {} {
send_user "Yay\n"
}
trap { # trap sigwinch and pass it to the child we spawned
set rows [stty rows]
set cols [stty columns]
stty rows $rows columns $cols < $spawn_out(slave,name)
} WINCH
spawn bash
interact {
interact -re "HOT" {
yay
}
expect {
fuzz yay
}
}
If i run this and type "HOT" it responds with "Yay". As expected, it read my keys. But if i type
echo fuzz
The "expect" clause doesnt get triggered. Also "echo HOT" wont trigger anything either.
So is this possible or am I missing somthing. Perhaps I'd need to emulate interact in some kind of "expect, continue"-loop. Its just important that everything works normally in the shell..
Suggestions anyone?

Answer 1

You can use the expect_background command. From the man page:
takes the same arguments as expect, however it returns immediately. Patterns are tested whenever new input arrives.
You can modify your initial script like this:
#!/usr/bin/expect
proc yay {} {
send_user "Yay\n"
}
trap { # trap sigwinch and pass it to the child we spawned
set rows [stty rows]
set cols [stty columns]
stty rows $rows columns $cols < $spawn_out(slave,name)
} WINCH
spawn bash
expect_background {
fuzz yay
}
interact -re "HOT" {
yay
}