rustc-dev-guide/src/generic_parameters_summary.md

Generic parameter definitions

This chapter will discuss how rustc tracks what generic parameters are introduced by an item. For example given some struct defined via struct Foo<T> how does rustc track that Foo defines some type parameter T and nothing else?

This will not cover how we track generic parameters introduced via for<'a> syntax (i.e. in where clauses or fn types), which is covered elsewhere in the chapter on Binders .