The script is in tools/ rather than thrown away, because two lanes are
writing Flan in the old spelling right now and their files need the same
pass at merge.
It works on forms, not on text: a keyword becomes a dot only where it sits
in a field-label position inside a brace, so an enum member in value
position, a map key inside an EDN string and a type-position {K V} are all
left alone. :keys keeps its colon -- it names no field.
print-str, print-i64, print-f64, print-bytes, print-line and newline leave
the prelude. print and println are the whole printing surface now, and print
is the better call at every one of the sites that used them: it is the same
structural walk without the newline, so the no-newline case the family was
kept for is covered, and it takes the value as it is. The old print-i64
forced an explicit (i64 x) at every call site, because this language widens
nothing implicitly; that cast is gone from 127 places.
Dropping it moves one answer. hash-grid returns u64, and the cast through
the signed printer showed sand-headless's hash as -2851001042534928384.
print routes a u64 through flan_u64_to_bytes, so it now prints
15595743031174623232 — the same 64 bits, read as the unsigned number they
are. The pinned expectation follows the correction.
test-flan-dev.el and test_session.ml both reached for print-line as "a name
the prelude has"; they reach for rand-seed instead.
The reload path had never seen a restart-case or a handler-bind: the
acceptance table's dev build proves whole-program codegen with cells, but not
Emit.redefinition, where the callees are declares or cell loads and the restart
frame is an alloca in a module the process was not built with. Driving it found
a hole step 1 left - a lifted clause was numbered by its position in the whole
program's lifted list, so the name was neither stable against an unrelated
handler-bind being added nor attributable to the function it came out of, and
redefining a function that established a handler died in llc with an undefined
value.
A clause is now named after its parent - handler/step/0/Missing - and carries
Tast.fn.fparent, which is what lets a redefinition module emit the clauses
belonging to the bodies it is replacing and nothing else. They are hidden for
the same reason a redefined body is: taking the address of an interposable
symbol would resolve to the host's copy, so the module would install the very
handler it was replacing. A clause is reached by address from its parent and
from nowhere else, so it is kept out of the cell and registry machinery
entirely rather than given a slot nobody uses.
test_dev.ml now sends a third evaluation: step redefined to a restart-case
whose frame is an alloca in the new module, whose guarded call goes through the
host's cell, and whose transfer starts in a handler and crosses probe, which
the host was compiled with. The transcript's fourth line is the clause's value.
The piece between an editor and everything else. One long-lived Session, the
program it belongs to launched and owned by the same process, and a socket that
takes forms and installs them. What it adds over flan reload is that the
session persists - a defvar added by one evaluation is part of what the next is
checked against - and that it owns the build, which is what makes its layout
rules describe the process actually running rather than a guess about it.
The protocol is s-expressions rather than bencode, and I changed my mind about
that. The case for nREPL was reusing a designed op set and not re-litigating
session identity, but with the client ours too there is no CIDER to be
compatible with, its eval is string-in/string-out with no slot for which form
from which file, and Emacs already has read and prin1. So: one sexp per
message, length framed because the payload contains newlines. No parsing code
on the editor side, and on this side the parser is the language's own reader,
where :op is already a keyword and Flan source is already a string literal. An
nREPL front end can sit on the same Session later; it should not gate the
editor.
Two silent failures the daemon refuses to have. The agent socket is chosen by
the daemon and forced through FLAN_AGENT_SOCKET before spawning, because a
program's source has to name some path and a daemon that guessed would compile,
build and deliver a module to nobody. And delivery is checked: agent/start
returning 0 means a socket was bound, not that anyone connected, so a failed
connect or a reply that is not ok becomes an error the editor sees.
It waits for the program to bind before accepting an evaluation, since one
arriving first fails for a reason that reads like a compiler bug, and it
accepts with a timeout so a program that has exited takes the daemon with it
instead of leaving an editor waiting on a socket nobody serves.
