Can I use multiple maps with a single map ?

For example;

map $ngxvar1 $myvar1 {
default 0;
~*string 1;
}
map $ngxvar2 $myvar2 {
default 0;
~*string 1;
}
map $ngxvar3 $myvar3 {
default 0;
~*string 1;
$myvar1 1;
$myvar2 1;
}

This way I would only have one IF $myvar3 ....., but obviously this example doesn't work, is this possible ?