Final answer:
Type checking for an anonymous function expression ensures that the function is used with expected input and output types as per the static semantics of the language, checked at compile time.
Step-by-step explanation:
Type checking of an anonymous function expression involves verifying at compile-time that the function is used with the correct types of inputs and outputs as expected.
This is part of static semantics, where the language compiler checks source code for type correctness without running the program. For instance, in a statically typed language, if an anonymous function is expected to take an integer and return a string, the type checker ensures that any invocation of this function adheres to this signature.