Joseph Ferano
26c53e0a19
The mechanical half, ahead of the parser change that needs it. tools/unit-return.py
fills the empty slot with () and rewrites Unit as () wherever a type is spelled --
(Fn [i32] Unit), (Map i32 Unit), a return type written out.
Deciding whether a defn already had a return type is the whole difficulty, and
the script does it the way parse.ml did: is_type_form is transcribed rather than
improved, because being identical to the parser it replaces is what makes the
sweep meaning-preserving. It is re-runnable, so the lanes that branched before
this can have the same pass at merge:
python3 tools/unit-return.py .
python3 tools/unit-return.py --in-strings test/test_flan.ml test/test_acceptance.ml \
test/test_session.ml emacs/test-flan-dev.el emacs/test-flan-mode.el
python3 tools/unit-return.py --raw-ml lib/prelude.ml
python3 tools/unit-return.py --in-html web/index.html
-v logs every defn it saw and what it decided, which is how a sweep of 440 sites
gets reviewed at all. Embedded modes pool a file's type declarations across all
its fragments, because a snippet split across concatenation -- decls ^ "(defn f
[s [u8]] Cursor ...)" -- cannot see the names the other half declared; pooled
names count only in bare-symbol position, for the same reason the prelude's do.
A fragment that cuts off mid-form is skipped rather than guessed at. Five sites
in test_flan.ml still needed a hand, and they are in this commit.
Two things ride along because the sweep needs them: parse.ml reads a lone () as
the return type of a function with no body, which was not a shape the old
optional slot could produce; and the map refusals name () rather than Unit, since
that is now the spelling a caller wrote.
14 lines
463 B
Plaintext
14 lines
463 B
Plaintext
(defconst nums [4 i32] [4 8 15 16])
|
|
|
|
;; `some` unwraps Some and early-returns None from *this* function.
|
|
(defn doubled-first [s [i32]] (Option i32)
|
|
(Some (* 2 (some (index-of-i32 s 15)))))
|
|
|
|
(defn main [] ()
|
|
(match (doubled-first (slice nums 0 4))
|
|
(Some i) (do (print i) (println "")) ; 4
|
|
None (println "not found"))
|
|
(match (index-of-i32 (slice nums 0 4) 99)
|
|
(Some i) (do (print i) (println ""))
|
|
None (println "not found")))
|