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Code Issues 1 Releases Wiki Activity

Add proper optional arguments.

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Use &opt in the parameter list to get optional arguments.
This commit is contained in:
Calvin Rose
2019-03-12 00:23:14 -04:00
parent a246877c1e
commit d42bdf2443
9 changed files with 92 additions and 61 deletions
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40
src/core/specials.c
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@@ -643,16 +643,17 @@ static JanetSlot janetc_fn(JanetFopts opts, int32_t argn, const Janet *argv) {
JanetSlot ret;
Janet head;
JanetScope fnscope;
int32_t paramcount, argi, parami, arity, defindex, i;
int32_t paramcount, argi, parami, arity, min_arity, max_arity, defindex, i;
JanetFopts subopts = janetc_fopts_default(c);
const Janet *params;
const char *errmsg = NULL;
/* Function flags */
int vararg = 0;
int fixarity = 1;
int allow_extra = 0;
int selfref = 0;
int seenamp = 0;
int seenopt = 0;
/* Begin function */
c->scope->flags |= JANET_SCOPE_CLOSURE;
@@ -683,19 +684,32 @@ static JanetSlot janetc_fn(JanetFopts opts, int32_t argn, const Janet *argv) {
Janet param = params[i];
if (janet_checktype(param, JANET_SYMBOL)) {
/* Check for varargs and unfixed arity */
if ((!seenamp) &&
(0 == janet_cstrcmp(janet_unwrap_symbol(param), "&"))) {
seenamp = 1;
fixarity = 0;
if (i == paramcount - 1) {
if (!janet_cstrcmp(janet_unwrap_symbol(param), "&")) {
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 = "variable argument symbol in unexpected location";
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 {
janetc_nameslot(c, janet_unwrap_symbol(param), janetc_farslot(c));
}
@@ -704,6 +718,9 @@ static JanetSlot janetc_fn(JanetFopts opts, int32_t argn, const Janet *argv) {
}
}
max_arity = (vararg || allow_extra) ? INT32_MAX : arity;
if (!seenopt) min_arity = arity;
/* Check for self ref */
if (selfref) {
JanetSlot slot = janetc_farslot(c);
@@ -715,17 +732,20 @@ static JanetSlot janetc_fn(JanetFopts opts, int32_t argn, const Janet *argv) {
/* Compile function body */
if (parami + 1 == argn) {
janetc_emit(c, JOP_RETURN_NIL);
} else for (argi = parami + 1; argi < argn; argi++) {
} else {
for (argi = parami + 1; argi < argn; argi++) {
subopts.flags = (argi == (argn - 1)) ? JANET_FOPTS_TAIL : JANET_FOPTS_DROP;
janetc_value(subopts, argv[argi]);
if (c->result.status == JANET_COMPILE_ERROR)
goto error2;
}
}
/* Build function */
def = janetc_pop_funcdef(c);
def->arity = arity;
if (fixarity) def->flags |= JANET_FUNCDEF_FLAG_FIXARITY;
def->min_arity = min_arity;
def->max_arity = max_arity;
if (vararg) def->flags |= JANET_FUNCDEF_FLAG_VARARG;
if (selfref) def->name = janet_unwrap_symbol(head);