Quantified Values
Quantified Values inhabit Quantified Types. This concept maps exactly to the programming concept of iterators, so we will just steal that syntax and use it here.
Iterators
A naked iterator looks much like a for loop.
for i:Integer in ls yield i+1
Containers
Iterators can fill containers,
like sets
{for a:Integer in s yield a*a}
or lists
[for a:Integer in s yield a*a]
or maps.
{for a:Integer in s yield a=a*a}