Performs macro expansion:

Expandable trees

A term of one of the following shapes:

Ident(<term macro>) Select(<any qualifier>, <term macro>) TypeApply(<any of the above>, <targs>) Apply(...Apply(<any of the above>, <args1>)...<argsN>)

Macro expansion

First of all macroExpandXXX: 1) If necessary desugars the expandee to fit into the default expansion scheme that is understood by macroExpandWithRuntime / macroExpandWithoutRuntime

Then macroExpandWithRuntime: 2) Checks whether the expansion needs to be delayed 3) Loads macro implementation using macroMirror 4) Synthesizes invocation arguments for the macro implementation 5) Checks that the result is a tree or an expr bound to this universe

Finally macroExpandXXX: 6) Validates the expansion against the white list of supported tree shapes 7) Typechecks the result as required by the circumstances of the macro application

If -Ymacro-debug-lite is enabled, you will get basic notifications about macro expansion along with macro expansions logged in the form that can be copy/pasted verbatim into REPL.

If -Ymacro-debug-verbose is enabled, you will get detailed log of how exactly this function performs class loading and method resolution in order to load the macro implementation. The log will also include other non-trivial steps of macro expansion.