b-rich / macrostep Goto Github PK

`macrostep-mode' is a minor mode for interactively stepping through
the expansion of macros in Emacs Lisp source code. It lets you see
exactly what happens at each step of the expansion process by
pretty-printing the expanded forms inline in the source buffer, which
is read-only while macro expansions are visible. You can expand and
collapse macro forms one step at a time, and evaluate or instrument
them for debugging with Edebug as normal (but see "Bugs and known
limitations", below). Single-stepping through the expansion is useful
for debugging macros that expand into another macro form, especially
one like `lexical-let' that does significant rewriting. These can be
difficult to debug with Emacs' built-in `macroexpand' because
`macroexpand' continues expansion until the top-level form is no
longer a macro call.

macrostep-mode adds some simple additional fontification to
macro-expanded text. The heads of macro sub-forms are fontified using
`macrostep-macro-face'. Uninterned symbols (gensyms) are fontified
based on which step in the expansion created them, to distinguish them
from normal symbols and from other gensyms with the same print
name. Use `customize-group' with the "macrostep" group to customize
these faces.

See the "Commentary" section of "macrostep.el" for more.