Since C# 5.0, async and await are contextual keywords. Contextual keywords
do have a particular meaning in some contexts, but are not reserved and therefore can be used as variable names.
int await = 42; // Noncompliant, but compiles
int async = 42; // Noncompliant, but compiles
Keywords, on the other hand, are always reserved and
therefore are not valid variable names.
int abstract = 42; // Error CS1585: Member modifier 'abstract' must precede the member type and name
int foreach = 42; // Error CS1519: Invalid token 'foreach' in class, struct, or interface member declaration
To avoid any confusion, it is best to not use async and await as identifiers.
int someVariableName = 42;
int someOtherVariableName = 42;
