X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=herp.c;fp=herp.c;h=2b3ee4929e586b1fee558ab45e0dd461b0fa89c4;hb=e158cf8f49978f42fb2380d3f84c5df963a39a3f;hp=0000000000000000000000000000000000000000;hpb=8c79ea4a9df54fc083be365d107dd81036057864;p=p5sagit%2FFunction-Parameters.git

diff --git a/herp.c b/herp.c
new file mode 100644
index 0000000..2b3ee49
--- /dev/null
+++ b/herp.c
@@ -0,0 +1,164 @@
+
+#define DEFSTRUCT(T) typedef struct T T; struct T
+
+DEFSTRUCT(ParamInit) {
+	SV *name;
+	OP *init;
+};
+
+#define DEFVECTOR(T, B) DEFSTRUCT(T) { \
+	B (*data); \
+	size_t used, size; \
+}
+
+DEFVECTOR(ParamInitVec, ParamInit);
+DEFVECTOR(ParamVec, SV *);
+
+DEFSTRUCT(ParamSpec) {
+	SV *invocant;
+	ParamVec positional_required;
+	ParamInitVec positional_optional;
+	ParamVec named_required;
+	ParamInitVec named_optional;
+	SV *slurpy;
+};
+
+#define DEFVECTOR_CLEAR(T, N, F) static void N(T *p) { \
+	while (p->used) { \
+		p->used--; \
+		F(p->data[p->used]); \
+	} \
+	Safefree(p->data); \
+	p->data =NULL; \
+	p->size = 0; \
+} static void N(T *)
+
+static void pi_clear(ParamInit pi) {
+	if (pi.name) {
+		SvREFCNT_dec(pi.name);
+	}
+	if (pi.init) {
+		op_free(pi.init);
+	}
+}
+
+DEFVECTOR_CLEAR(ParamVec, pv_clear, SvREFCNT_dec);
+DEFVECTOR_CLEAR(ParamInitVec, piv_clear, pi_clear);
+
+static void ps_free(ParamSpec *ps) {
+	if (ps->invocant) {
+		SvREFCNT_dec(ps->invocant);
+		ps->invocant = NULL;
+	}
+	pv_clear(&ps->positional_required);
+	piv_clear(&ps->positional_optional);
+	pv_clear(&ps->named_required);
+	piv_clear(&ps->named_optional);
+	if (ps->slurpy) {
+		SvREFCNT_dec(ps->slurpy);
+		ps->slurpy = NULL;
+	}
+	Safefree(ps);
+}
+
+static int args_min(const ParamSpec *ps) {
+	int n = 0;
+	if (ps->invocant) {
+		n++;
+	}
+	n += ps->positional_required.used;
+	n += ps->named_required.used * 2;
+	return n;
+}
+
+static int args_max(const ParamSpec *ps) {
+	int n = 0;
+	if (ps->invocant) {
+		n++;
+	}
+	n += ps->positional_required.used;
+	n += ps->positional_optional.used;
+	if (ps->named_required.used || ps->named_optional.used || ps->slurpy) {
+		n = -1;
+	}
+	return n;
+}
+
+static size_t count_positional_params(const ParamSpec *ps) {
+	return ps->positional_required.used + ps->positional_optional.used;
+}
+
+static size_t count_named_params(const ParamSpec *ps) {
+	return ps->named_required.used + ps->named_optional.used;
+}
+
+static void gen(ParamSpec *ps) {
+	int amin = args_min(ps);
+	if (amin > 0) {
+		printf("croak 'not enough' if @_ < %d;\n", amin);
+	}
+	int amax = args_max(ps);
+	if (amax >= 0) {
+		printf("croak 'too many' if @_ > %d;\n", amax);
+	}
+	size_t named_params = count_named_params(ps);
+	if (named_params || (ps->slurpy && SvPV_nolen(ps->slurpy)[0] == '%')) {
+		size_t t = named_params + !!ps->invocant;
+		printf("croak 'odd' if (@_ - %zu) > 0 && (@_ - %zu) % 2;\n", t, t);
+	}
+	if (ps->invocant) {
+		printf("%s = shift @_;\n", SvPV_nolen(ps->invocant));
+	}
+	// XXX (...) = @_;
+	size_t positional_params = count_positional_params(ps);
+	for (size_t i = 0; i < ps->positional_optional.used; i++) {
+		printf("%*sif (@_ < %zu) {\n", (int)i * 2, "", positional_params - i);
+	}
+	for (size_t i = 0; i < ps->positional_optional.used; i++) {
+		ParamInit *pi = &ps->positional_optional.data[i];
+		printf("%*s  %s = %p;\n", (int)(ps->positional_optional.used - i - 1) * 2, "", SvPV_nolen(pi->name), pi->init);
+		printf("%*s}\n", (int)(ps->positional_optional.used - i - 1) * 2, "");
+	}
+	if (named_params) {
+		printf("if (@_ > %zu) {\n", positional_params);
+		printf("  my $_b = '';\n");
+		printf("  my $_i = %zu;\n", positional_params);
+		printf("  while ($_i < @_) {\n");
+		printf("    my $_k = $_[$_i];\n");
+		size_t req = ps->named_required.used;
+		for (size_t i = 0; i < named_params; i++) {
+			printf("    ");
+			if (i) {
+				printf("els");
+			}
+			SV *param = i >= req ? ps->named_optional.data[i - req] : ps->named_required.data[i];
+			printf("if ($_k eq '%s') {\n", SvPV_nolen(param) + 1);
+			printf("      %s = $_[$_i + 1];\n", SvPV_nolen(param));
+			printf("      vec($_b, %zu, 1) = 1;\n", i);
+			printf("    }\n");
+		}
+		printf("    else {\n");
+		if (ps->slurpy) {
+			const char *slurpy = SvPV_nolen(ps->slurpy);
+			if (slurpy[0] == '%') {
+				printf("      $%s{$_k} = $_[$_i + 1];\n", slurpy + 1);
+			} else {
+				printf("      push %s, $_k, $_[$_i + 1];\n", slurpy);
+			}
+		} else {
+			printf("      croak 'no such param ' . $_k;\n");
+		}
+		printf("    }\n");
+		printf("    $_i += 2;\n");
+		printf("  }\n");
+		if (ps->named_required.used) {
+			printf("  if (($_b & pack('b*', '1' x %zu)) ne pack('b*', '1' x %zu)) {\n", ps->named_required.used, ps->named_required.used);
+			printf("    croak 'missing required named args';\n"); // XXX
+			printf("  }\n");
+		}
+		for (size_t i = 0; i < ps->named_optional.used; i++) {
+			printf("  %s = %p unless vec $_k, %zu, 1;\n", SvPV_nolen(ps->named_optional[i].name), ps->named_optional[i].init, ps->named_required.used + i);
+		}
+		printf("}\n");
+	}
+}