inform7/inter/bytecode-module/Chapter 4/The Insert Construct.w

[InsertInstruction::] The Insert Construct.

Defining the insert construct.

@h Definition.
For what this does and why it is used, see //inter: Data Packages in Textual Inter//.
But please use it as little as possible: in an ideal world it would be abolished.

=
void InsertInstruction::define_construct(void) {
	inter_construct *IC = InterInstruction::create_construct(INSERT_IST, I"insert");
	InterInstruction::specify_syntax(IC, I"insert TEXT TEXT TEXT NUMBER");
	InterInstruction::data_extent_always(IC, 4);
	InterInstruction::permit(IC, INSIDE_PLAIN_PACKAGE_ICUP);
	METHOD_ADD(IC, CONSTRUCT_READ_MTID, InsertInstruction::read);
	METHOD_ADD(IC, CONSTRUCT_TRANSPOSE_MTID, InsertInstruction::transpose);
	METHOD_ADD(IC, CONSTRUCT_VERIFY_MTID, InsertInstruction::verify);
	METHOD_ADD(IC, CONSTRUCT_WRITE_MTID, InsertInstruction::write);
}

@h Instructions.
In bytecode, the frame of an |insert| instruction is laid out with the
compulsory words -- see //Inter Nodes// -- followed by:

@d TEXT_INSERT_IFLD (DATA_IFLD + 0)
@d REPLACING_INSERT_IFLD (DATA_IFLD + 1)
@d PROVENANCEFILE_INSERT_IFLD (DATA_IFLD + 2)
@d PROVENANCELINE_INSERT_IFLD (DATA_IFLD + 3)

=
inter_error_message *InsertInstruction::new(inter_bookmark *IBM,
	text_stream *text, text_stream *replacing, 
	filename *file, inter_ti line_number,
	inter_ti level, struct inter_error_location *eloc) {
	TEMPORARY_TEXT(file_as_text)
	if (file) WRITE_TO(file_as_text, "%f", file);
	inter_warehouse *warehouse = InterBookmark::warehouse(IBM);
	inter_package *pack = InterBookmark::package(IBM);
	inter_ti ID = InterWarehouse::create_text(warehouse, pack);
	Str::copy(InterWarehouse::get_text(warehouse, ID), text);
	inter_ti RID = InterWarehouse::create_text(warehouse, pack);
	Str::copy(InterWarehouse::get_text(warehouse, RID), replacing);
	inter_ti FID = InterWarehouse::create_text(warehouse, pack);
	Str::copy(InterWarehouse::get_text(warehouse, FID), file_as_text);
	inter_tree_node *P = Inode::new_with_4_data_fields(IBM, INSERT_IST,
		/* TEXT_INSERT_IFLD: */           ID,
		/* REPLACING_INSERT_IFLD: */      RID,
		/* PROVENANCEFILE_INSERT_IFLD: */ FID,
		/* PROVENANCELINE_INSERT_IFLD: */ line_number,
		eloc, level);
	inter_error_message *E = VerifyingInter::instruction(pack, P); if (E) return E;
	NodePlacement::move_to_moving_bookmark(P, IBM);
	return NULL;
}

void InsertInstruction::transpose(inter_construct *IC, inter_tree_node *P, inter_ti *grid,
	inter_ti grid_extent, inter_error_message **E) {
	P->W.instruction[TEXT_INSERT_IFLD] = grid[P->W.instruction[TEXT_INSERT_IFLD]];
}

@ Verification consists only of sanity checks.

=
void InsertInstruction::verify(inter_construct *IC, inter_tree_node *P,
	inter_package *owner, inter_error_message **E) {
	*E = VerifyingInter::text_field(owner, P, TEXT_INSERT_IFLD);
	if (*E) return;
	*E = VerifyingInter::text_field(owner, P, REPLACING_INSERT_IFLD);
	if (*E) return;
	*E = VerifyingInter::text_field(owner, P, PROVENANCEFILE_INSERT_IFLD);
	if (*E) return;
}

@h Creating from textual Inter syntax.

=
void InsertInstruction::read(inter_construct *IC, inter_bookmark *IBM, inter_line_parse *ilp,
	inter_error_location *eloc, inter_error_message **E) {
	text_stream *rq = ilp->mr.exp[0];
	text_stream *repq = ilp->mr.exp[1];
	text_stream *fn = ilp->mr.exp[2];
	text_stream *lc = ilp->mr.exp[3];
	TEMPORARY_TEXT(raw)
	TEMPORARY_TEXT(replacing)
	TEMPORARY_TEXT(file_as_text)
	*E = TextualInter::parse_literal_text(raw, rq, 0, Str::len(rq), eloc);
	if (*E == NULL)
		*E = TextualInter::parse_literal_text(replacing, repq, 0, Str::len(repq), eloc);
	if (*E == NULL)
		*E = TextualInter::parse_literal_text(file_as_text, fn, 0, Str::len(fn), eloc);
	if (*E == NULL) {
		filename *F = NULL;
		if (Str::len(file_as_text) > 0) F = Filenames::from_text(file_as_text);
		inter_ti line_number = 0;
		if (Str::len(lc) > 0) line_number = (inter_ti) Str::atoi(lc, 0);
		*E = InsertInstruction::new(IBM, raw, replacing, F, line_number,
			(inter_ti) ilp->indent_level, eloc);
	}
	DISCARD_TEXT(raw)
	DISCARD_TEXT(replacing)
	DISCARD_TEXT(file_as_text)
}

@h Writing to textual Inter syntax.

=
void InsertInstruction::write(inter_construct *IC, OUTPUT_STREAM, inter_tree_node *P) {
	text_stream *insertion = InsertInstruction::insertion(P);
	text_stream *replacing = InsertInstruction::replacing(P);
	WRITE("insert ");
	TextualInter::write_text(OUT, insertion);
	WRITE(" ");
	TextualInter::write_text(OUT, replacing);
	WRITE(" ");
	Provenance::write(OUT, InsertInstruction::provenance(P));
}

@h Access functions.

=
text_stream *InsertInstruction::insertion(inter_tree_node *P) {
	if (P == NULL) return NULL;
	if (Inode::isnt(P, INSERT_IST)) return NULL;
	return Inode::ID_to_text(P, P->W.instruction[TEXT_INSERT_IFLD]);
}

text_stream *InsertInstruction::replacing(inter_tree_node *P) {
	if (P == NULL) return NULL;
	if (Inode::isnt(P, INSERT_IST)) return NULL;
	return Inode::ID_to_text(P, P->W.instruction[REPLACING_INSERT_IFLD]);
}

text_provenance InsertInstruction::provenance(inter_tree_node *P) {
	if (P == NULL) return Provenance::nowhere();
	if (Inode::isnt(P, INSERT_IST)) return Provenance::nowhere();
	return Provenance::at_file_and_line(
		Inode::ID_to_text(P, P->W.instruction[PROVENANCEFILE_INSERT_IFLD]),
		(int) P->W.instruction[PROVENANCELINE_INSERT_IFLD]);
}