<p>
A Go <i>program execution</i> is modeled as a set of goroutine executions,
together with a mapping <i>W</i> that specifies the write-like operation that each read-like operation reads from.
(Multiple executions of the same program can have different program executions.)
</p>

<p>
<b>Requirement 2</b>:
For a given program execution, the mapping <i>W</i>, when limited to synchronizing operations,

Initially, the bound type parameters are known but the map is empty.
During type unification, if a new type argument <code>A</code> is inferred,
the respective mapping <code>P ➞ A</code> from type parameter to argument
is added to the map.
Conversely, when comparing types, a known type argument
(a type argument for which a map entry already exists)