Better pretty printer.

git-svn-id: http://svn.drobilla.net/resp/resp@269 ad02d1e2-f140-0410-9f75-f8b11f17cedd

1 files changed, 87 insertions, 20 deletions

diff --git a/src/pprint.cpp b/src/pprint.cpp
index 391609a..76796d7 100644
--- a/src/pprint.cpp
+++ b/src/pprint.cpp
@@ -73,34 +73,101 @@ operator<<(ostream& out, const AST* ast)
 	return out << "?";
 }
 
+enum TupleStyle {
+	STYLE_ONE_LINE, // Entire tuple printed on one line
+	STYLE_ALIGN, // Align all elements aligned after opening '('
+	STYLE_CALL // Call with all arguments aligned after head
+};
+
+static bool
+can_one_line(const AST* ast, const unsigned max_width, unsigned& width, unsigned& depth)
+{
+	static const unsigned MAX_DEPTH = 3;
+
+	ostringstream ss;
+	ss << ast;
+	if ((width += ss.str().length()) >= max_width)
+		return false;
+
+	const ATuple* tup = ast->to<const ATuple*>();
+	if (tup) {
+		if (++depth >= MAX_DEPTH)
+			return false;
+
+		for (ATuple::const_iterator i = tup->begin(); i != tup->end(); ++i) {
+			ostringstream ss;
+			ss << *i;
+			width += ss.str().length();
+			if (!can_one_line(*i, max_width, width, depth))
+				return false;
+		}
+	}
+
+	return true;
+}
+	
+static TupleStyle
+tuple_style(const ATuple* tup, const unsigned max_width, unsigned& indent)
+{
+	unsigned depth = 0;
+	unsigned width = indent;
+	if (can_one_line(tup, max_width, width, depth))
+		return STYLE_ONE_LINE;
+
+	if (tup->to<const ADef*>() || tup->to<const AFn*>()) {
+		indent += 2;
+		return STYLE_CALL;
+	}
+	
+	if (tup->to<const ACall*>()) {
+		indent += tup->head()->str().length() + 1;
+		return STYLE_CALL;
+	}
+
+	return STYLE_ALIGN;
+}
+
+static void
+newline(ostream& out, unsigned indent)
+{
+	out << endl;
+	for (unsigned i = 0; i < indent; ++i)
+		out << " ";
+}
+	
 void
 pprint_internal(ostream& out, const AST* ast, unsigned indent)
 {
 	const ATuple* tup = ast->to<const ATuple*>();
-	if (tup && !tup->empty()) {
-		ATuple::const_iterator i = tup->begin() + 1;
-		const string head = tup->head()->str();
-		const ASymbol* headSym = tup->head()->to<const ASymbol*>();
+	if (tup) {
 		out << "(";
-		pprint_internal(out, tup->head(), indent);
-		unsigned child_indent = indent;
-		if (tup->size() > 1) {
-			out << " ";
-			if (headSym && (headSym->cppstr == "fn" || headSym->cppstr == "def")) {
-				out << *i;
-				child_indent = indent + 2;
-			} else {
-				child_indent += head.length() + 2;
-				pprint_internal(out, *i, child_indent);
+		unsigned               child_indent = indent + 1;
+		ATuple::const_iterator i            = tup->begin();
+		if (i != tup->end()) {
+			const TupleStyle style = tuple_style(tup, 80, child_indent);
+			pprint_internal(out, *i++, indent + 1); // Print head
+			switch (style) {
+			case STYLE_ONE_LINE:
+				while (i != tup->end())
+					out << " " << *i++;
+				break;
+			case STYLE_ALIGN:
+				while (i != tup->end()) {
+					newline(out, indent + 1);
+					pprint_internal(out, *i++, child_indent);
+				}
+				break;
+			case STYLE_CALL:
+				out << " ";
+				pprint_internal(out, *i, child_indent); // Print first argument
+				while (++i != tup->end()) {
+					newline(out, child_indent);
+					pprint_internal(out, *i, child_indent);
+				}
+				break;
 			}
 		}
-		while (++i != tup->end()) {
-			out << endl << string().insert(0, child_indent, ' ');
-			pprint_internal(out, *i, child_indent);
-		}
 		out << ")";
-		if (headSym && (headSym->cppstr == "fn" || headSym->cppstr == "def"))
-			out << endl << string().insert(0, indent + 2, ' ');
 	} else {
 		out << ast;
 	}