Add named arguments with the &named symbol.

Similar to &keys, but more ergonomic.
This commit is contained in:
Calvin Rose 2022-06-12 13:50:17 -05:00
parent 6d188f6e44
commit 87fc339c45
4 changed files with 93 additions and 36 deletions

View File

@ -2,6 +2,9 @@
All notable changes to this project will be documented in this file.
## Unreleased - ???
- Allow using `&named` in function prototypes for named arguments. This is a more ergonomic
variant of `&keys` that isn't as redundant, more self documenting, and allows extension to
things like default arguments.
- Add `debugger` - an easy to use debugger function that just takes a fiber.
- `dofile` will now start a debugger on errors if the environment it is passed has `:debug` set.
- Add `debugger-on-status` function, which can be passed to `run-context` to start a debugger on

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@ -553,6 +553,10 @@ static JanetAssembleResult janet_asm1(JanetAssembler *parent, Janet source, int
x = janet_get1(s, janet_ckeywordv("vararg"));
if (janet_truthy(x)) def->flags |= JANET_FUNCDEF_FLAG_VARARG;
/* Check structarg */
x = janet_get1(s, janet_ckeywordv("structarg"));
if (janet_truthy(x)) def->flags |= JANET_FUNCDEF_FLAG_STRUCTARG;
/* Check source */
x = janet_get1(s, janet_ckeywordv("source"));
if (janet_checktype(x, JANET_STRING)) def->source = janet_unwrap_string(x);
@ -884,6 +888,10 @@ static Janet janet_disasm_vararg(JanetFuncDef *def) {
return janet_wrap_boolean(def->flags & JANET_FUNCDEF_FLAG_VARARG);
}
static Janet janet_disasm_structarg(JanetFuncDef *def) {
return janet_wrap_boolean(def->flags & JANET_FUNCDEF_FLAG_STRUCTARG);
}
static Janet janet_disasm_constants(JanetFuncDef *def) {
JanetArray *constants = janet_array(def->constants_length);
for (int32_t i = 0; i < def->constants_length; i++) {
@ -933,6 +941,7 @@ Janet janet_disasm(JanetFuncDef *def) {
janet_table_put(ret, janet_ckeywordv("bytecode"), janet_disasm_bytecode(def));
janet_table_put(ret, janet_ckeywordv("source"), janet_disasm_source(def));
janet_table_put(ret, janet_ckeywordv("vararg"), janet_disasm_vararg(def));
janet_table_put(ret, janet_ckeywordv("structarg"), janet_disasm_structarg(def));
janet_table_put(ret, janet_ckeywordv("name"), janet_disasm_name(def));
janet_table_put(ret, janet_ckeywordv("slotcount"), janet_disasm_slotcount(def));
janet_table_put(ret, janet_ckeywordv("constants"), janet_disasm_constants(def));
@ -986,6 +995,7 @@ JANET_CORE_FN(cfun_disasm,
if (!janet_cstrcmp(kw, "source")) return janet_disasm_source(f->def);
if (!janet_cstrcmp(kw, "name")) return janet_disasm_name(f->def);
if (!janet_cstrcmp(kw, "vararg")) return janet_disasm_vararg(f->def);
if (!janet_cstrcmp(kw, "structarg")) return janet_disasm_structarg(f->def);
if (!janet_cstrcmp(kw, "slotcount")) return janet_disasm_slotcount(f->def);
if (!janet_cstrcmp(kw, "constants")) return janet_disasm_constants(f->def);
if (!janet_cstrcmp(kw, "sourcemap")) return janet_disasm_sourcemap(f->def);

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@ -822,6 +822,7 @@ static JanetSlot janetc_fn(JanetFopts opts, int32_t argn, const Janet *argv) {
int selfref = 0;
int seenamp = 0;
int seenopt = 0;
int namedargs = 0;
/* Begin function */
c->scope->flags |= JANET_SCOPE_CLOSURE;
@ -846,6 +847,9 @@ static JanetSlot janetc_fn(JanetFopts opts, int32_t argn, const Janet *argv) {
/* Keep track of destructured parameters */
JanetSlot *destructed_params = NULL;
JanetSlot *named_params = NULL;
JanetTable *named_table = NULL;
JanetSlot named_slot;
/* Compile function parameters */
params = janet_unwrap_tuple(argv[parami]);
@ -853,49 +857,74 @@ static JanetSlot janetc_fn(JanetFopts opts, int32_t argn, const Janet *argv) {
arity = paramcount;
for (i = 0; i < paramcount; i++) {
Janet param = params[i];
if (janet_checktype(param, JANET_SYMBOL)) {
if (namedargs) {
if (!janet_checktype(param, JANET_SYMBOL)) {
errmsg = "only named arguments can follow &named";
goto error;
}
Janet key = janet_wrap_keyword(janet_unwrap_symbol(param));
janet_table_put(named_table, key, param);
janet_v_push(named_params, janetc_farslot(c));
} else if (janet_checktype(param, JANET_SYMBOL)) {
/* Check for varargs and unfixed arity */
if (!janet_cstrcmp(janet_unwrap_symbol(param), "&")) {
if (seenamp) {
errmsg = "& in unexpected location";
goto error;
} else if (i == paramcount - 1) {
allow_extra = 1;
const uint8_t *sym = janet_unwrap_symbol(param);
if (sym[0] == '&') {
if (!janet_cstrcmp(sym, "&")) {
if (seenamp) {
errmsg = "& in unexpected location";
goto error;
} else if (i == paramcount - 1) {
allow_extra = 1;
arity--;
} else if (i == paramcount - 2) {
vararg = 1;
arity -= 2;
} else {
errmsg = "& in unexpected location";
goto error;
}
seenamp = 1;
} else if (!janet_cstrcmp(sym, "&opt")) {
if (seenopt) {
errmsg = "only one &opt allowed";
goto error;
} else if (i == paramcount - 1) {
errmsg = "&opt cannot be last item in parameter list";
goto error;
}
min_arity = i;
arity--;
} else if (i == paramcount - 2) {
vararg = 1;
arity -= 2;
} else {
errmsg = "& in unexpected location";
goto error;
}
seenamp = 1;
} else if (!janet_cstrcmp(janet_unwrap_symbol(param), "&opt")) {
if (seenopt) {
errmsg = "only one &opt allowed";
goto error;
} else if (i == paramcount - 1) {
errmsg = "&opt cannot be last item in parameter list";
goto error;
}
min_arity = i;
arity--;
seenopt = 1;
} else if (!janet_cstrcmp(janet_unwrap_symbol(param), "&keys")) {
if (seenamp) {
errmsg = "&keys in unexpected location";
goto error;
} else if (i == paramcount - 2) {
seenopt = 1;
} else if (!janet_cstrcmp(sym, "&keys")) {
if (seenamp) {
errmsg = "&keys in unexpected location";
goto error;
} else if (i == paramcount - 2) {
vararg = 1;
structarg = 1;
arity -= 2;
} else {
errmsg = "&keys in unexpected location";
goto error;
}
seenamp = 1;
} else if (!janet_cstrcmp(sym, "&named")) {
if (seenamp) {
errmsg = "&named in unexpected location";
goto error;
}
vararg = 1;
structarg = 1;
arity -= 2;
arity = i;
seenamp = 1;
namedargs = 1;
named_table = janet_table(10);
named_slot = janetc_farslot(c);
} else {
errmsg = "&keys in unexpected location";
goto error;
janetc_nameslot(c, sym, janetc_farslot(c));
}
seenamp = 1;
} else {
janetc_nameslot(c, janet_unwrap_symbol(param), janetc_farslot(c));
janetc_nameslot(c, sym, janetc_farslot(c));
}
} else {
janet_v_push(destructed_params, janetc_farslot(c));
@ -914,6 +943,14 @@ static JanetSlot janetc_fn(JanetFopts opts, int32_t argn, const Janet *argv) {
}
janet_v_free(destructed_params);
/* Compile named arguments */
if (namedargs) {
Janet param = janet_wrap_table(named_table);
destructure(c, param, named_slot, defleaf, NULL);
janetc_freeslot(c, named_slot);
janet_v_free(named_params);
}
max_arity = (vararg || allow_extra) ? INT32_MAX : arity;
if (!seenopt) min_arity = arity;

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@ -80,5 +80,12 @@
"table rawget regression"
(table/new -1))
# Named arguments
(defn named-arguments
[&named bob sally joe]
(+ bob sally joe))
(assert (= 15 (named-arguments :bob 3 :sally 5 :joe 7)) "named arguments 1")
(end-suite)