Utilities for printing debug messages.
eprint message prints to stderr message, followed by a newline and flush. This is
the same as prerr_endline.
eprints message a sexp_of_a prints to stderr message and a as a sexp, followed
by a newline and flush.
eprint_s sexp prints sexp to stderr, followed by a newline and a flush.
eprintf message arg1 ... argn prints to stderr message, with sprintf-style format
characters instantiated, followed by a newline and flush.
Debug.Make produces a debug function used to wrap a function to display arguments
before calling and display results after returning.
am, ams, and amf output a source code position and backtrace to stderr. amf
accepts a printf-style format string. ams accepts a message, value, and sexp
converter for that value. Typical usage looks like:
...;
Debug.am [%here];
...;
Debug.amf [%here] "hello (%s, %s)" (X.to_string x) (Y.to_string y);
...;
Debug.ams [%here] "hello" (x, y) <:sexp_of< X.t * Y.t >>;
...;
The am* functions output source code positions in the standard format
"FILE:LINE:COL", which means that one can use a tool like emacs grep-mode on a buffer
containing debug messages to step through one's code by stepping through the
messages.