From 241e92c09f8d0a9a42c74768a960d938db245ca9 Mon Sep 17 00:00:00 2001
From: NeilBrown <neil@brown.name>
Date: Sat, 11 May 2019 11:30:30 +1000
Subject: [PATCH] oceani: move "complex types" earlier.

I think this fits better before "language elements",
as part of "data structures".  Nearly everything it needs
is defined by there.

Signed-off-by: NeilBrown <neil@brown.name>
---
 csrc/oceani.mdc | 462 ++++++++++++++++++++++++------------------------
 1 file changed, 231 insertions(+), 231 deletions(-)

diff --git a/csrc/oceani.mdc b/csrc/oceani.mdc
index 02968bb..b47383a 100644
--- a/csrc/oceani.mdc
+++ b/csrc/oceani.mdc
@@ -1525,6 +1525,237 @@ Each `exec` can return a value, which may be `Tnone` but must be non-NULL;
 		return ret;
 	}
 
+### Complex types
+
+Now that we have the shape of the interpreter in place we can add some
+complex types and connected them in to the data structures and the
+different phases of parse, analyse, print, interpret.
+
+For now, just arrays.
+
+#### Arrays
+
+Arrays can be declared by giving a size and a type, as `[size]type' so
+`freq:[26]number` declares `freq` to be an array of 26 numbers.  The
+size can be an arbitrary expression which is evaluated when the name
+comes into scope.
+
+Arrays cannot be assigned.  When pointers are introduced we will also
+introduce array slices which can refer to part or all of an array -
+the assignment syntax will create a slice.  For now, an array can only
+ever be referenced by the name it is declared with.  It is likely that
+a "`copy`" primitive will eventually be define which can be used to
+make a copy of an array with controllable depth.
+
+###### type union fields
+
+	struct {
+		int size;
+		struct variable *vsize;
+		struct type *member;
+	} array;
+
+###### value union fields
+	struct {
+		struct value *elmnts;
+	} array;
+
+###### value functions
+
+	static struct value array_prepare(struct type *type)
+	{
+		struct value ret;
+
+		ret.type = type;
+		ret.array.elmnts = NULL;
+		return ret;
+	}
+
+	static struct value array_init(struct type *type)
+	{
+		struct value ret;
+		int i;
+
+		ret.type = type;
+		if (type->array.vsize) {
+			mpz_t q;
+			mpz_init(q);
+			mpz_tdiv_q(q, mpq_numref(type->array.vsize->val.num),
+			           mpq_denref(type->array.vsize->val.num));
+			type->array.size = mpz_get_si(q);
+			mpz_clear(q);
+		}
+		ret.array.elmnts = calloc(type->array.size,
+		                          sizeof(ret.array.elmnts[0]));
+		for (i = 0; ret.array.elmnts && i < type->array.size; i++)
+			ret.array.elmnts[i] = val_init(type->array.member);
+		return ret;
+	}
+
+	static void array_free(struct value val)
+	{
+		int i;
+
+		if (val.array.elmnts)
+			for (i = 0; i < val.type->array.size; i++)
+				free_value(val.array.elmnts[i]);
+		free(val.array.elmnts);
+	}
+
+	static int array_compat(struct type *require, struct type *have)
+	{
+		if (have->compat != require->compat)
+			return 0;
+		/* Both are arrays, so we can look at details */
+		if (!type_compat(require->array.member, have->array.member, 0))
+			return 0;
+		if (require->array.vsize == NULL && have->array.vsize == NULL)
+			return require->array.size == have->array.size;
+
+		return require->array.vsize == have->array.vsize;
+	}
+
+	static void array_print_type(struct type *type, FILE *f)
+	{
+		fputs("[", f);
+		if (type->array.vsize) {
+			struct binding *b = type->array.vsize->name;
+			fprintf(f, "%.*s]", b->name.len, b->name.txt);
+		} else
+			fprintf(f, "%d]", type->array.size);
+		type_print(type->array.member, f);
+	}
+
+	static struct type array_prototype = {
+		.prepare = array_prepare,
+		.init = array_init,
+		.print_type = array_print_type,
+		.compat = array_compat,
+		.free = array_free,
+	};
+
+###### type grammar
+
+	| [ NUMBER ] Type ${
+		$0 = calloc(1, sizeof(struct type));
+		*($0) = array_prototype;
+		$0->array.member = $<4;
+		$0->array.vsize = NULL;
+		{
+		struct parse_context *c = config2context(config);
+		char tail[3];
+		mpq_t num;
+		if (number_parse(num, tail, $2.txt) == 0)
+			tok_err(c, "error: unrecognised number", &$2);
+		else if (tail[0])
+			tok_err(c, "error: unsupported number suffix", &$2);
+		else {
+			$0->array.size = mpz_get_ui(mpq_numref(num));
+			if (mpz_cmp_ui(mpq_denref(num), 1) != 0) {
+				tok_err(c, "error: array size must be an integer",
+				        &$2);
+			} else if (mpz_cmp_ui(mpq_numref(num), 1UL << 30) >= 0)
+				tok_err(c, "error: array size is too large",
+				        &$2);
+			mpq_clear(num);
+		}
+		$0->next= c->anon_typelist;
+		c->anon_typelist = $0;
+		}
+	}$
+
+	| [ IDENTIFIER ] Type ${ {
+		struct parse_context *c = config2context(config);
+		struct variable *v = var_ref(c, $2.txt);
+
+		if (!v)
+			tok_err(config2context(config), "error: name undeclared", &$2);
+		else if (!v->constant)
+			tok_err(config2context(config), "error: array size must be a constant", &$2);
+
+		$0 = calloc(1, sizeof(struct type));
+		*($0) = array_prototype;
+		$0->array.member = $<4;
+		$0->array.size = 0;
+		$0->array.vsize = v;
+		$0->next= c->anon_typelist;
+		c->anon_typelist = $0;
+	} }$
+
+###### parse context
+
+	struct type *anon_typelist;
+
+###### free context types
+
+	while (context.anon_typelist) {
+		struct type *t = context.anon_typelist;
+
+		context.anon_typelist = t->next;
+		free(t);
+	}
+
+###### Binode types
+	Index,
+
+###### variable grammar
+
+	| Variable [ Expression ] ${ {
+		struct binode *b = new(binode);
+		b->op = Index;
+		b->left = $<1;
+		b->right = $<3;
+		$0 = b;
+	} }$
+
+###### print binode cases
+	case Index:
+		print_exec(b->left, -1, 0);
+		printf("[");
+		print_exec(b->right, -1, 0);
+		printf("]");
+		break;
+
+###### propagate binode cases
+	case Index:
+		/* left must be an array, right must be a number,
+		 * result is the member type of the array
+		 */
+		propagate_types(b->right, c, ok, Tnum, 0);
+		t = propagate_types(b->left, c, ok, NULL, rules & Rnoconstant);
+		if (!t || t->compat != array_compat) {
+			type_err(c, "error: %1 cannot be indexed", prog, t, 0, NULL);
+			*ok = 0;
+			return NULL;
+		} else {
+			if (!type_compat(type, t->array.member, rules)) {
+				type_err(c, "error: have %1 but need %2", prog,
+				         t->array.member, rules, type);
+				*ok = 0;
+			}
+			return t->array.member;
+		}
+		break;
+
+###### interp binode cases
+	case Index: {
+		mpz_t q;
+		long i;
+
+		lleft = linterp_exec(b->left);
+		right = interp_exec(b->right);
+		mpz_init(q);
+		mpz_tdiv_q(q, mpq_numref(right.num), mpq_denref(right.num));
+		i = mpz_get_si(q);
+		mpz_clear(q);
+
+		if (i >= 0 && i < lleft->type->array.size)
+			lrv = &lleft->array.elmnts[i];
+		else
+			rv = val_init(lleft->type->array.member);
+		break;
+	}
+
 ## Language elements
 
 Each language element needs to be parsed, printed, analysed,
@@ -3313,237 +3544,6 @@ defined.
 		break;
 	}
 
-## Complex types
-
-Now that we have the shape of the interpreter in place we can add some
-complex types and connected them in to the data structures and the
-different phases of parse, analyse, print, interpret.
-
-For now, just arrays.
-
-### Arrays
-
-Arrays can be declared by giving a size and a type, as `[size]type' so
-`freq:[26]number` declares `freq` to be an array of 26 numbers.  The
-size can be an arbitrary expression which is evaluated when the name
-comes into scope.
-
-Arrays cannot be assigned.  When pointers are introduced we will also
-introduce array slices which can refer to part or all of an array -
-the assignment syntax will create a slice.  For now, an array can only
-ever be referenced by the name it is declared with.  It is likely that
-a "`copy`" primitive will eventually be define which can be used to
-make a copy of an array with controllable depth.
-
-###### type union fields
-
-	struct {
-		int size;
-		struct variable *vsize;
-		struct type *member;
-	} array;
-
-###### value union fields
-	struct {
-		struct value *elmnts;
-	} array;
-
-###### value functions
-
-	static struct value array_prepare(struct type *type)
-	{
-		struct value ret;
-
-		ret.type = type;
-		ret.array.elmnts = NULL;
-		return ret;
-	}
-
-	static struct value array_init(struct type *type)
-	{
-		struct value ret;
-		int i;
-
-		ret.type = type;
-		if (type->array.vsize) {
-			mpz_t q;
-			mpz_init(q);
-			mpz_tdiv_q(q, mpq_numref(type->array.vsize->val.num),
-			           mpq_denref(type->array.vsize->val.num));
-			type->array.size = mpz_get_si(q);
-			mpz_clear(q);
-		}
-		ret.array.elmnts = calloc(type->array.size,
-		                          sizeof(ret.array.elmnts[0]));
-		for (i = 0; ret.array.elmnts && i < type->array.size; i++)
-			ret.array.elmnts[i] = val_init(type->array.member);
-		return ret;
-	}
-
-	static void array_free(struct value val)
-	{
-		int i;
-
-		if (val.array.elmnts)
-			for (i = 0; i < val.type->array.size; i++)
-				free_value(val.array.elmnts[i]);
-		free(val.array.elmnts);
-	}
-
-	static int array_compat(struct type *require, struct type *have)
-	{
-		if (have->compat != require->compat)
-			return 0;
-		/* Both are arrays, so we can look at details */
-		if (!type_compat(require->array.member, have->array.member, 0))
-			return 0;
-		if (require->array.vsize == NULL && have->array.vsize == NULL)
-			return require->array.size == have->array.size;
-
-		return require->array.vsize == have->array.vsize;
-	}
-
-	static void array_print_type(struct type *type, FILE *f)
-	{
-		fputs("[", f);
-		if (type->array.vsize) {
-			struct binding *b = type->array.vsize->name;
-			fprintf(f, "%.*s]", b->name.len, b->name.txt);
-		} else
-			fprintf(f, "%d]", type->array.size);
-		type_print(type->array.member, f);
-	}
-
-	static struct type array_prototype = {
-		.prepare = array_prepare,
-		.init = array_init,
-		.print_type = array_print_type,
-		.compat = array_compat,
-		.free = array_free,
-	};
-
-###### type grammar
-
-	| [ NUMBER ] Type ${
-		$0 = calloc(1, sizeof(struct type));
-		*($0) = array_prototype;
-		$0->array.member = $<4;
-		$0->array.vsize = NULL;
-		{
-		struct parse_context *c = config2context(config);
-		char tail[3];
-		mpq_t num;
-		if (number_parse(num, tail, $2.txt) == 0)
-			tok_err(c, "error: unrecognised number", &$2);
-		else if (tail[0])
-			tok_err(c, "error: unsupported number suffix", &$2);
-		else {
-			$0->array.size = mpz_get_ui(mpq_numref(num));
-			if (mpz_cmp_ui(mpq_denref(num), 1) != 0) {
-				tok_err(c, "error: array size must be an integer",
-				        &$2);
-			} else if (mpz_cmp_ui(mpq_numref(num), 1UL << 30) >= 0)
-				tok_err(c, "error: array size is too large",
-				        &$2);
-			mpq_clear(num);
-		}
-		$0->next= c->anon_typelist;
-		c->anon_typelist = $0;
-		}
-	}$
-
-	| [ IDENTIFIER ] Type ${ {
-		struct parse_context *c = config2context(config);
-		struct variable *v = var_ref(c, $2.txt);
-
-		if (!v)
-			tok_err(config2context(config), "error: name undeclared", &$2);
-		else if (!v->constant)
-			tok_err(config2context(config), "error: array size must be a constant", &$2);
-
-		$0 = calloc(1, sizeof(struct type));
-		*($0) = array_prototype;
-		$0->array.member = $<4;
-		$0->array.size = 0;
-		$0->array.vsize = v;
-		$0->next= c->anon_typelist;
-		c->anon_typelist = $0;
-	} }$
-
-###### parse context
-
-	struct type *anon_typelist;
-
-###### free context types
-
-	while (context.anon_typelist) {
-		struct type *t = context.anon_typelist;
-
-		context.anon_typelist = t->next;
-		free(t);
-	}
-
-###### Binode types
-	Index,
-
-###### variable grammar
-
-	| Variable [ Expression ] ${ {
-		struct binode *b = new(binode);
-		b->op = Index;
-		b->left = $<1;
-		b->right = $<3;
-		$0 = b;
-	} }$
-
-###### print binode cases
-	case Index:
-		print_exec(b->left, -1, 0);
-		printf("[");
-		print_exec(b->right, -1, 0);
-		printf("]");
-		break;
-
-###### propagate binode cases
-	case Index:
-		/* left must be an array, right must be a number,
-		 * result is the member type of the array
-		 */
-		propagate_types(b->right, c, ok, Tnum, 0);
-		t = propagate_types(b->left, c, ok, NULL, rules & Rnoconstant);
-		if (!t || t->compat != array_compat) {
-			type_err(c, "error: %1 cannot be indexed", prog, t, 0, NULL);
-			*ok = 0;
-			return NULL;
-		} else {
-			if (!type_compat(type, t->array.member, rules)) {
-				type_err(c, "error: have %1 but need %2", prog,
-				         t->array.member, rules, type);
-				*ok = 0;
-			}
-			return t->array.member;
-		}
-		break;
-
-###### interp binode cases
-	case Index: {
-		mpz_t q;
-		long i;
-
-		lleft = linterp_exec(b->left);
-		right = interp_exec(b->right);
-		mpz_init(q);
-		mpz_tdiv_q(q, mpq_numref(right.num), mpq_denref(right.num));
-		i = mpz_get_si(q);
-		mpz_clear(q);
-
-		if (i >= 0 && i < lleft->type->array.size)
-			lrv = &lleft->array.elmnts[i];
-		else
-			rv = val_init(lleft->type->array.member);
-		break;
-	}
-
 ### Finally the whole program.
 
 Somewhat reminiscent of Pascal a (current) Ocean program starts with
-- 
2.43.0