AST - (minor) Move dump_as_rust to ast/dump.cpp

1 files changed, 1098 insertions, 0 deletions

diff --git a/src/ast/dump.cpp b/src/ast/dump.cpp
new file mode 100644
index 00000000..ad7c4ef7
--- /dev/null
+++ b/src/ast/dump.cpp
@@ -0,0 +1,1098 @@
+/*
+ * MRustC - Mutabah's Rust Compiler
+ * - By John Hodge (Mutabah/thePowersGang)
+ * 
+ * ast/dump.cpp
+ * - Dumps the AST of a crate as rust code (annotated)
+ */
+#include <ast/crate.hpp>
+#include <ast/ast.hpp>
+#include <ast/expr.hpp>
+#include <main_bindings.hpp>
+
+#include <cpp_unpack.h>
+
+#define IS(v, c)    (dynamic_cast<c*>(&v) != 0)
+#define WRAPIF_CMD(v, t)  || IS(v, t)
+#define WRAPIF(uniq_ptr, class1, ...) do { auto& _v = *(uniq_ptr); if( IS(_v, class1) CC_ITERATE(WRAPIF_CMD, (_v), __VA_ARGS__) ) { paren_wrap(uniq_ptr); } else { AST::NodeVisitor::visit(uniq_ptr); } } while(0)
+
+class RustPrinter:
+    public AST::NodeVisitor
+{
+    ::std::ostream& m_os;
+    int m_indent_level;
+    bool m_expr_root;   //!< used to allow 'if' and 'match' to behave differently as standalone exprs
+public:
+    RustPrinter(::std::ostream& os):
+        m_os(os),
+        m_indent_level(0),
+        m_expr_root(false)
+    {}
+    
+    void handle_module(const AST::Module& mod);
+    void handle_struct(const AST::Struct& s);
+    void handle_enum(const AST::Enum& s);
+    void handle_trait(const AST::Trait& s);
+
+    void handle_function(bool is_pub, const ::std::string& name, const AST::Function& f);
+
+    virtual bool is_const() const override { return true; }
+    virtual void visit(AST::ExprNode_Block& n) override {
+        if( n.m_is_unsafe ) {
+            m_os << "unsafe ";
+        }
+        m_os << "{";
+        inc_indent();
+        if( n.m_local_mod )
+        {
+            handle_module(*n.m_local_mod);
+        }
+        bool is_first = true;
+        for( auto& child : n.m_nodes )
+        {
+            if(is_first) {
+                is_first = false;
+            } else {
+                m_os << ";";
+            }
+            m_os << "\n";
+            m_os << indent();
+            m_expr_root = true;
+            if( !child.get() )
+                m_os << "/* nil */";
+            else
+                AST::NodeVisitor::visit(child);
+        }
+        if( !n.m_yields_final_value )
+            m_os << ";";
+        m_os << "\n";
+        dec_indent();
+        m_os << indent() << "}";
+    }
+    virtual void visit(AST::ExprNode_Macro& n) override {
+        m_expr_root = false;
+        m_os << n.m_name << "!( /* TODO: Macro TT */ )";
+    }
+    virtual void visit(AST::ExprNode_Flow& n) override {
+        m_expr_root = false;
+        switch(n.m_type)
+        {
+        case AST::ExprNode_Flow::RETURN:    m_os << "return ";  break;
+        case AST::ExprNode_Flow::BREAK:     m_os << "break ";  break;
+        case AST::ExprNode_Flow::CONTINUE:  m_os << "continue ";  break;
+        }
+        AST::NodeVisitor::visit(n.m_value);
+    }
+    virtual void visit(AST::ExprNode_LetBinding& n) override {
+        m_expr_root = false;
+        m_os << "let ";
+        print_pattern(n.m_pat, false);
+        m_os << ": ";
+        print_type(n.m_type);
+        m_os << " = ";
+        AST::NodeVisitor::visit(n.m_value);
+    }
+    virtual void visit(AST::ExprNode_Assign& n) override {
+        m_expr_root = false;
+        AST::NodeVisitor::visit(n.m_slot);
+        switch(n.m_op)
+        {
+        case AST::ExprNode_Assign::NONE:    m_os << "  = ";  break;
+        case AST::ExprNode_Assign::ADD:     m_os << " += ";  break;
+        case AST::ExprNode_Assign::SUB:     m_os << " -= ";  break;
+        case AST::ExprNode_Assign::MUL:     m_os << " *= ";  break;
+        case AST::ExprNode_Assign::DIV:     m_os << " /= ";  break;
+        case AST::ExprNode_Assign::MOD:     m_os << " %= ";  break;
+        case AST::ExprNode_Assign::AND:     m_os << " &= ";  break;
+        case AST::ExprNode_Assign::OR:      m_os << " |= ";  break;
+        case AST::ExprNode_Assign::XOR:     m_os << " ^= ";  break;
+        case AST::ExprNode_Assign::SHR:     m_os << " >>= ";  break;
+        case AST::ExprNode_Assign::SHL:     m_os << " <<= ";  break;
+        }
+        AST::NodeVisitor::visit(n.m_value);
+    }
+    virtual void visit(AST::ExprNode_CallPath& n) override {
+        m_expr_root = false;
+        m_os << n.m_path;
+        m_os << "(";
+        bool is_first = true;
+        for( auto& arg : n.m_args )
+        {
+            if(is_first) {
+                is_first = false;
+            } else {
+                m_os << ", ";
+            }
+            AST::NodeVisitor::visit(arg);
+        }
+        m_os << ")";
+    }
+    virtual void visit(AST::ExprNode_CallMethod& n) override {
+        m_expr_root = false;
+        WRAPIF( n.m_val
+            , AST::ExprNode_Deref, AST::ExprNode_UniOp
+            , AST::ExprNode_Cast, AST::ExprNode_BinOp, AST::ExprNode_Assign
+            , AST::ExprNode_Match, AST::ExprNode_If, AST::ExprNode_IfLet, AST::ExprNode_Match
+            );
+        m_os << "." << n.m_method;
+        m_os << "(";
+        bool is_first = true;
+        for( auto& arg : n.m_args )
+        {
+            if(is_first) {
+                is_first = false;
+            } else {
+                m_os << ", ";
+            }
+            AST::NodeVisitor::visit(arg);
+        }
+        m_os << ")";
+    }
+    virtual void visit(AST::ExprNode_CallObject& n) override {
+        m_expr_root = false;
+        m_os << "(";
+        AST::NodeVisitor::visit(n.m_val);
+        m_os << ")(";
+        bool is_first = true;
+        for( auto& arg : n.m_args )
+        {
+            if(is_first) {
+                is_first = false;
+            } else {
+                m_os << ", ";
+            }
+            AST::NodeVisitor::visit(arg);
+        }
+        m_os << ")";
+    }
+    virtual void visit(AST::ExprNode_Loop& n) override {
+        bool expr_root = m_expr_root;
+        m_expr_root = false;
+        
+        switch(n.m_type)
+        {
+        case AST::ExprNode_Loop::LOOP:
+            m_os << "loop";
+            break;
+        case AST::ExprNode_Loop::WHILE:
+            m_os << "while ";
+            AST::NodeVisitor::visit(n.m_cond);
+            break;
+        case AST::ExprNode_Loop::WHILELET:
+            m_os << "while let ";
+            print_pattern(n.m_pattern, true);
+            m_os << " = ";
+            AST::NodeVisitor::visit(n.m_cond);
+            break;
+        case AST::ExprNode_Loop::FOR:
+            m_os << "while for ";
+            print_pattern(n.m_pattern, true);
+            m_os << " in ";
+            AST::NodeVisitor::visit(n.m_cond);
+            break;
+        }
+        
+        if( expr_root )
+        {
+            m_os << "\n";
+            m_os << indent();
+        }
+        else
+        {
+            m_os << " ";
+        }
+
+        AST::NodeVisitor::visit(n.m_code);
+    }
+    virtual void visit(AST::ExprNode_Match& n) override {
+        bool expr_root = m_expr_root;
+        m_expr_root = false;
+        m_os << "match ";
+        AST::NodeVisitor::visit(n.m_val);
+        
+        if(expr_root)
+        {
+            m_os << "\n";
+            m_os << indent() << "{\n";
+        }
+        else
+        {
+            m_os << " {\n";
+            inc_indent();
+        }
+        
+        for( auto& arm : n.m_arms )
+        {
+            m_os << indent();
+            bool is_first = true;
+            for( const auto& pat : arm.m_patterns ) {
+                if(!is_first)
+                    m_os << "|";
+                is_first = false;
+                print_pattern(pat, true);
+            }
+            if( arm.m_cond )
+            {
+                m_os << " if ";
+                AST::NodeVisitor::visit(arm.m_cond);
+            }
+            m_os << " => ";
+            // Increase indent, but don't print. Causes nested blocks to be indented above the match
+            inc_indent();
+            AST::NodeVisitor::visit(arm.m_code);
+            dec_indent();
+            m_os << ",\n";
+        }
+        
+        if(expr_root)
+        {
+            m_os << indent() << "}";
+        }
+        else
+        {
+            m_os << indent() << "}";
+            dec_indent();
+        }
+    }
+    virtual void visit(AST::ExprNode_If& n) override {
+        bool expr_root = m_expr_root;
+        m_expr_root = false;
+        m_os << "if ";
+        AST::NodeVisitor::visit(n.m_cond);
+        
+        visit_if_common(expr_root, n.m_true, n.m_false);
+    }
+    virtual void visit(AST::ExprNode_IfLet& n) override {
+        bool expr_root = m_expr_root;
+        m_expr_root = false;
+        m_os << "if let ";
+        print_pattern(n.m_pattern, true);
+        m_os << " = ";
+        AST::NodeVisitor::visit(n.m_value);
+        
+        visit_if_common(expr_root, n.m_true, n.m_false);
+    }
+    void visit_if_common(bool expr_root, const ::std::unique_ptr<AST::ExprNode>& tv, const ::std::unique_ptr<AST::ExprNode>& fv)
+    {
+        if( expr_root )
+        {
+            m_os << "\n";
+            m_os << indent();
+        }
+        else
+        {
+            m_os << " ";
+        }
+
+        bool is_block = (dynamic_cast<const AST::ExprNode_Block*>(&*tv) != nullptr);
+        if( !is_block ) m_os << "{ ";
+        AST::NodeVisitor::visit(tv);
+        if( !is_block ) m_os << " }";
+        if(fv.get())
+        {
+            if( expr_root )
+            {
+                m_os << "\n";
+                m_os << indent() << "else";
+                // handle chained if statements nicely
+                if( IS(*fv, AST::ExprNode_If) || IS(*fv, AST::ExprNode_IfLet) ) {
+                    m_expr_root = true;
+                    m_os << " ";
+                }
+                else
+                    m_os << "\n" << indent();
+            }
+            else
+            {
+                m_os << " else ";
+            }
+            AST::NodeVisitor::visit(fv);
+        }
+    }
+    virtual void visit(AST::ExprNode_Closure& n) override {
+        m_expr_root = false;
+        m_os << "|";
+        bool is_first = true;
+        for( const auto& arg : n.m_args )
+        {
+            if(!is_first)   m_os << ", ";
+            is_first = false;
+            print_pattern(arg.first, false);
+            m_os << ": ";
+            print_type(arg.second);
+        }
+        m_os << "| ->";
+        print_type(n.m_return);
+        m_os << " ";
+        AST::NodeVisitor::visit(n.m_code);
+    }
+    virtual void visit(AST::ExprNode_Integer& n) override {
+        m_expr_root = false;
+        switch(n.m_datatype)
+        {
+        case CORETYPE_INVAL:    break;
+        case CORETYPE_BOOL:
+        case CORETYPE_STR:
+            break;
+        case CORETYPE_CHAR:
+            m_os << "'\\u{" << ::std::hex << n.m_value << ::std::dec << "}'";
+            break;
+        case CORETYPE_F32:
+        case CORETYPE_F64:
+            break;
+        case CORETYPE_U8:
+        case CORETYPE_U16:
+        case CORETYPE_U32:
+        case CORETYPE_U64:
+        case CORETYPE_UINT:
+        case CORETYPE_ANY:
+            m_os << "0x" << ::std::hex << n.m_value << ::std::dec;
+            break;
+        case CORETYPE_I8:
+        case CORETYPE_I16:
+        case CORETYPE_I32:
+        case CORETYPE_I64:
+        case CORETYPE_INT:
+            m_os << (int64_t)n.m_value;
+            //m_os << "0x" << ::std::hex << n.m_value << ::std::dec;
+            break;
+        }
+    }
+    virtual void visit(AST::ExprNode_Float& n) override {
+        m_expr_root = false;
+        switch(n.m_datatype)
+        {
+        case CORETYPE_ANY:
+        case CORETYPE_F32:
+        case CORETYPE_F64:
+            m_os.precision(10);
+            m_os << n.m_value;
+            break;
+        default:
+            break;
+        }
+    }
+    virtual void visit(AST::ExprNode_Bool& n) override {
+        m_expr_root = false;
+        if( n.m_value )
+            m_os << "true";
+        else
+            m_os << "false";
+    }
+    virtual void visit(AST::ExprNode_String& n) override {
+        m_expr_root = false;
+        m_os << "\"" << n.m_value << "\"";
+    }
+    virtual void visit(AST::ExprNode_ByteString& n) override {
+        m_expr_root = false;
+        m_os << "b\"" << n.m_value << "\"";
+    }
+    
+    virtual void visit(AST::ExprNode_StructLiteral& n) override {
+        m_expr_root = false;
+        m_os << n.m_path << " {\n";
+        inc_indent();
+        for( const auto& i : n.m_values )
+        {
+            m_os << indent() << i.first << ": ";
+            AST::NodeVisitor::visit(i.second);
+            m_os << ",\n";
+        }
+        if( n.m_base_value.get() )
+        {
+            m_os << indent() << ".. ";
+            AST::NodeVisitor::visit(n.m_base_value);
+            m_os << "\n";
+        }
+        m_os << indent() << "}";
+        dec_indent();
+    }
+    virtual void visit(AST::ExprNode_Array& n) override {
+        m_expr_root = false;
+        m_os << "[";
+        if( n.m_size.get() )
+        {
+            AST::NodeVisitor::visit(n.m_values[0]);
+            m_os << "; ";
+            AST::NodeVisitor::visit(n.m_size);
+        }
+        else {
+            for( auto& item : n.m_values )
+            {
+                AST::NodeVisitor::visit(item);
+                m_os << ", ";
+            }
+        }
+        m_os << "]";
+    }
+    virtual void visit(AST::ExprNode_Tuple& n) override {
+        m_expr_root = false;
+        m_os << "(";
+        for( auto& item : n.m_values )
+        {
+            AST::NodeVisitor::visit(item);
+            m_os << ", ";
+        }
+        m_os << ")";
+    }
+    virtual void visit(AST::ExprNode_NamedValue& n) override {
+        m_expr_root = false;
+        m_os << n.m_path;
+    }
+    virtual void visit(AST::ExprNode_Field& n) override {
+        m_expr_root = false;
+        WRAPIF( n.m_obj
+            , AST::ExprNode_Deref, AST::ExprNode_UniOp
+            , AST::ExprNode_Cast, AST::ExprNode_BinOp, AST::ExprNode_Assign
+            , AST::ExprNode_Match, AST::ExprNode_If, AST::ExprNode_IfLet, AST::ExprNode_Match
+            );
+        m_os << "." << n.m_name;
+    }
+    virtual void visit(AST::ExprNode_Index& n) override {
+        m_expr_root = false;
+        WRAPIF( n.m_obj
+            , AST::ExprNode_Deref, AST::ExprNode_UniOp
+            , AST::ExprNode_Cast, AST::ExprNode_BinOp, AST::ExprNode_Assign
+            , AST::ExprNode_Match, AST::ExprNode_If, AST::ExprNode_IfLet, AST::ExprNode_Match
+            );
+        m_os << "[";
+        AST::NodeVisitor::visit(n.m_idx);
+        m_os << "]";
+    }
+    virtual void visit(AST::ExprNode_Deref& n) override {
+        m_expr_root = false;
+        m_os << "*(";
+        AST::NodeVisitor::visit(n.m_value);
+        m_os << ")";
+    }
+    virtual void visit(AST::ExprNode_Cast& n) override {
+        m_expr_root = false;
+        AST::NodeVisitor::visit(n.m_value);
+        m_os << " as " << n.m_type;
+    }
+    virtual void visit(AST::ExprNode_BinOp& n) override {
+        m_expr_root = false;
+        WRAPIF(n.m_left
+            , AST::ExprNode_Cast, AST::ExprNode_BinOp
+            );
+        m_os << " ";
+        switch(n.m_type)
+        {
+        case AST::ExprNode_BinOp::CMPEQU: m_os << "=="; break;
+        case AST::ExprNode_BinOp::CMPNEQU:m_os << "!="; break;
+        case AST::ExprNode_BinOp::CMPLT:  m_os << "<";  break;
+        case AST::ExprNode_BinOp::CMPLTE: m_os << "<="; break;
+        case AST::ExprNode_BinOp::CMPGT:  m_os << ">";  break;
+        case AST::ExprNode_BinOp::CMPGTE: m_os << ">="; break;
+        case AST::ExprNode_BinOp::BOOLAND:m_os << "&&"; break;
+        case AST::ExprNode_BinOp::BOOLOR: m_os << "||"; break;
+        case AST::ExprNode_BinOp::BITAND: m_os << "&";  break;
+        case AST::ExprNode_BinOp::BITOR:  m_os << "|";  break;
+        case AST::ExprNode_BinOp::BITXOR: m_os << "^";  break;
+        case AST::ExprNode_BinOp::SHL:    m_os << "<<"; break;
+        case AST::ExprNode_BinOp::SHR:    m_os << ">>"; break;
+        case AST::ExprNode_BinOp::MULTIPLY: m_os << "*"; break;
+        case AST::ExprNode_BinOp::DIVIDE:   m_os << "/"; break;
+        case AST::ExprNode_BinOp::MODULO:   m_os << "%"; break;
+        case AST::ExprNode_BinOp::ADD:   m_os << "+"; break;
+        case AST::ExprNode_BinOp::SUB:   m_os << "-"; break;
+        case AST::ExprNode_BinOp::RANGE: m_os << ".."; break;
+        case AST::ExprNode_BinOp::RANGE_INC: m_os << "..."; break;
+        case AST::ExprNode_BinOp::PLACE_IN: m_os << "<-"; break;
+        }
+        m_os << " ";
+        if( IS(*n.m_right, AST::ExprNode_BinOp) )
+            paren_wrap(n.m_right);
+        else
+            AST::NodeVisitor::visit(n.m_right);
+    }
+    virtual void visit(AST::ExprNode_UniOp& n) override {
+        m_expr_root = false;
+        switch(n.m_type)
+        {
+        case AST::ExprNode_UniOp::NEGATE:   m_os << "-";    break;
+        case AST::ExprNode_UniOp::INVERT:   m_os << "!";    break;
+        case AST::ExprNode_UniOp::BOX:      m_os << "box ";    break;
+        case AST::ExprNode_UniOp::REF:    m_os << "&";    break;
+        case AST::ExprNode_UniOp::REFMUT: m_os << "&mut ";    break;
+        case AST::ExprNode_UniOp::QMARK: break;
+        }
+        
+        if( IS(*n.m_value, AST::ExprNode_BinOp) )
+            m_os << "(";
+        AST::NodeVisitor::visit(n.m_value);
+        if( IS(*n.m_value, AST::ExprNode_BinOp) )
+            m_os << ")";
+        switch(n.m_type)
+        {
+        case AST::ExprNode_UniOp::QMARK: m_os << "?"; break;
+        default:    break;
+        }
+    }
+
+
+private:
+    void paren_wrap(::std::unique_ptr<AST::ExprNode>& node) {
+        m_os << "(";
+        AST::NodeVisitor::visit(node);
+        m_os << ")";
+    }
+    
+    void print_attrs(const AST::MetaItems& attrs);
+    void print_params(const AST::GenericParams& params);
+    void print_bounds(const AST::GenericParams& params);
+    void print_pattern_tuple(const AST::Pattern::TuplePat& v, bool is_refutable);
+    void print_pattern(const AST::Pattern& p, bool is_refutable);
+    void print_type(const TypeRef& t);
+    
+    void inc_indent();
+    RepeatLitStr indent();
+    void dec_indent();
+};
+
+void Dump_Rust(const char *Filename, const AST::Crate& crate)
+{
+    ::std::ofstream os(Filename);
+    RustPrinter printer(os);
+    printer.handle_module(crate.root_module());
+}
+
+void RustPrinter::print_attrs(const AST::MetaItems& attrs)
+{
+    for(const auto& a : attrs.m_items)
+    {
+        m_os << indent() << "#[" << a << "]\n";
+    }
+}
+
+void RustPrinter::handle_module(const AST::Module& mod)
+{
+    bool need_nl = true;
+    
+    for( const auto& i : mod.items() )
+    {
+        if( !i.data.is_Use() )  continue ;
+        const auto& i_data = i.data.as_Use();
+        //if(need_nl) {
+        //    m_os << "\n";
+        //    need_nl = false;
+        //}
+        if( i_data.path == AST::Path() ) {
+            continue ;
+        }
+        m_os << indent() << (i.is_pub ? "pub " : "") << "use " << i_data;
+        if( i.name == "" )
+        {
+            m_os << "::*";
+        }
+        else if( i_data.path.nodes().back().name() != i.name )
+        {
+            m_os << " as " << i.name;
+        }
+        m_os << ";\n";
+    }
+    need_nl = true;
+    
+    for( const auto& item : mod.items() )
+    {
+        if( !item.data.is_Module() )    continue ;
+        const auto& e = item.data.as_Module();
+        
+        m_os << "\n";
+        m_os << indent() << (item.is_pub ? "pub " : "") << "mod " << item.name << "\n";
+        m_os << indent() << "{\n";
+        inc_indent();
+        handle_module(e);
+        dec_indent();
+        m_os << indent() << "}\n";
+        m_os << "\n";
+    }
+    
+    for( const auto& item : mod.items() )
+    {
+        if( !item.data.is_Type() )    continue ;
+        const auto& e = item.data.as_Type();
+        
+        if(need_nl) {
+            m_os << "\n";
+            need_nl = false;
+        }
+        print_attrs(item.data.attrs);
+        m_os << indent() << (item.is_pub ? "pub " : "") << "type " << item.name;
+        print_params(e.params());
+        m_os << " = " << e.type();
+        print_bounds(e.params());
+        m_os << ";\n";
+    }
+    need_nl = true;
+    
+    for( const auto& item : mod.items() )
+    {
+        if( !item.data.is_Struct() )    continue ;
+        const auto& e = item.data.as_Struct();
+        
+        m_os << "\n";
+        print_attrs(item.data.attrs);
+        m_os << indent() << (item.is_pub ? "pub " : "") << "struct " << item.name;
+        handle_struct(e);
+    }
+    
+    for( const auto& item : mod.items() )
+    {
+        if( !item.data.is_Enum() )    continue ;
+        const auto& e = item.data.as_Enum();
+        
+        m_os << "\n";
+        print_attrs(item.data.attrs);
+        m_os << indent() << (item.is_pub ? "pub " : "") << "enum " << item.name;
+        handle_enum(e);
+    }
+    
+    for( const auto& item : mod.items() )
+    {
+        if( !item.data.is_Trait() )    continue ;
+        const auto& e = item.data.as_Trait();
+        
+        m_os << "\n";
+        print_attrs(item.data.attrs);
+        m_os << indent() << (item.is_pub ? "pub " : "") << "trait " << item.name;
+        handle_trait(e);
+    }
+    
+    for( const auto& item : mod.items() )
+    {
+        if( !item.data.is_Static() )    continue ;
+        const auto& e = item.data.as_Static();
+        
+        if(need_nl) {
+            m_os << "\n";
+            need_nl = false;
+        }
+        print_attrs(item.data.attrs);
+        m_os << indent() << (item.is_pub ? "pub " : "");
+        switch( e.s_class() )
+        {
+        case AST::Static::CONST:  m_os << "const ";   break;
+        case AST::Static::STATIC: m_os << "static ";   break;
+        case AST::Static::MUT:    m_os << "static mut ";   break;
+        }
+        m_os << item.name << ": " << e.type() << " = ";
+        e.value().visit_nodes(*this);
+        m_os << ";\n";
+    }
+    
+    for( const auto& item : mod.items() )
+    {
+        if( !item.data.is_Function() )    continue ;
+        const auto& e = item.data.as_Function();
+        
+        m_os << "\n";
+        print_attrs(item.data.attrs);
+        handle_function(item.is_pub, item.name, e);
+    }
+
+    for( const auto& i : mod.impls() )
+    {
+        m_os << "\n";
+        m_os << indent() << "impl";
+        print_params(i.def().params());
+        if( i.def().trait().ent != AST::Path() )
+        {
+                m_os << " " << i.def().trait().ent << " for";
+        }
+        m_os << " " << i.def().type() << "\n";
+        
+        print_bounds(i.def().params());
+        m_os << indent() << "{\n";
+        inc_indent();
+        for( const auto& it : i.items() )
+        {
+            TU_MATCH_DEF(AST::Item, (*it.data), (e),
+            (
+                throw ::std::runtime_error(FMT("Unexpected item type in impl block - " << it.data->tag_str()));
+                ),
+            (None,
+                // Ignore, it's been deleted by #[cfg]
+                ),
+            (MacroInv,
+                // TODO: Dump macro invocations
+                ),
+            (Static,
+                m_os << indent();
+                switch(e.s_class())
+                {
+                case ::AST::Static::CONST:  m_os << "const ";   break;
+                case ::AST::Static::STATIC: m_os << "static ";  break;
+                case ::AST::Static::MUT:    m_os << "static mut ";  break;
+                }
+                m_os << it.name << ": " << e.type() << " = ";
+                e.value().visit_nodes(*this);
+                m_os << ";\n";
+                ),
+            (Type,
+                m_os << indent() << "type " << it.name << " = " << e.type() << ";\n";
+                ),
+            (Function,
+                handle_function(it.is_pub, it.name, e);
+                )
+            )
+        }
+        dec_indent();
+        m_os << indent() << "}\n";
+    }
+}
+
+void RustPrinter::print_params(const AST::GenericParams& params)
+{
+    if( params.ty_params().size() > 0 || params.lft_params().size() > 0 )
+    {
+        bool is_first = true;
+        m_os << "<";
+        // Lifetimes
+        for( const auto& p : params.lft_params() )
+        {
+            if( !is_first )
+                m_os << ", ";
+            m_os << "'" << p;
+            is_first = false;
+        }
+        // Types
+        for( const auto& p : params.ty_params() )
+        {
+            if( !is_first )
+                m_os << ", ";
+            m_os << p.name();
+            if( !p.get_default().is_wildcard() )
+                m_os << " = " << p.get_default();
+            is_first = false;
+        }
+        m_os << ">";
+    }
+}
+
+void RustPrinter::print_bounds(const AST::GenericParams& params)
+{
+    if( params.bounds().size() )
+    {
+        m_os << indent() << "where\n";
+        inc_indent();
+        bool is_first = true;
+        
+        for( const auto& b : params.bounds() )
+        {
+            if( !is_first )
+                m_os << ",\n";
+            is_first = false;
+            
+            m_os << indent();
+            TU_MATCH(AST::GenericBound, (b), (ent),
+            (Lifetime,
+                m_os << "'" << ent.test << ": '" << ent.bound;
+                ),
+            (TypeLifetime,
+                m_os << ent.type << ": '" << ent.bound;
+                ),
+            (IsTrait,
+                if( ent.hrls.size() > 0 ) {
+                    m_os << "for<'" << ::join(", '", ent.hrls) << "> ";
+                }
+                m_os << ent.type << ": " << ent.trait;
+                ),
+            (MaybeTrait,
+                m_os << ent.type << ": ?" << ent.trait;
+                ),
+            (NotTrait,
+                m_os << ent.type << ": !" << ent.trait;
+                ),
+            (Equality,
+                m_os << ent.type << ": =" << ent.replacement;
+                )
+            )
+        }
+        m_os << "\n";
+    
+        dec_indent();
+    }
+}
+
+void RustPrinter::print_pattern_tuple(const AST::Pattern::TuplePat& v, bool is_refutable)
+{
+    for(const auto& sp : v.start) {
+        print_pattern(sp, is_refutable);
+        m_os << ", ";
+    }
+    if( v.has_wildcard )
+    {
+        m_os << ".., ";
+        for(const auto& sp : v.end) {
+            print_pattern(sp, is_refutable);
+            m_os << ", ";
+        }
+    }
+}
+void RustPrinter::print_pattern(const AST::Pattern& p, bool is_refutable)
+{
+    if( p.binding().is_valid() ) {
+        if( p.binding().m_mutable )
+            m_os << "mut ";
+        switch(p.binding().m_type)
+        {
+        case ::AST::PatternBinding::Type::MOVE:
+            break;
+        case ::AST::PatternBinding::Type::REF:
+            m_os << "ref ";
+            break;
+        case ::AST::PatternBinding::Type::MUTREF:
+            m_os << "ref mut ";
+            break;
+        }
+        m_os << p.binding().m_name << "/*"<<p.binding().m_slot<<"*/";
+        // If binding is irrefutable, and would be binding against a wildcard, just emit the name
+        if( !is_refutable && p.data().is_Any() )
+        {
+            return ;
+        }
+        m_os << " @ ";
+    }
+    TU_MATCH(AST::Pattern::Data, (p.data()), (v),
+    (Any,
+        m_os << "_";
+        ),
+    (MaybeBind,
+        m_os << "_ /*?*/";
+        ),
+    (Macro,
+        m_os << *v.inv;
+        ),
+    (Box, {
+        const auto& v = p.data().as_Box();
+        m_os << "& ";
+        print_pattern(*v.sub, is_refutable);
+        }),
+    (Ref, {
+        const auto& v = p.data().as_Ref();
+        if(v.mut)
+            m_os << "&mut ";
+        else
+            m_os << "& ";
+        print_pattern(*v.sub, is_refutable);
+        }),
+    (Value,
+        m_os << v.start;
+        if( ! v.end.is_Invalid() ) {
+            m_os << " ... " << v.end;
+        }
+        ),
+    (StructTuple,
+        m_os << v.path << "(";
+        this->print_pattern_tuple(v.tup_pat, is_refutable);
+        m_os << ")";
+        ),
+    (Struct, {
+        const auto& v = p.data().as_Struct();
+        m_os << v.path << "(";
+        for(const auto& sp : v.sub_patterns) {
+            m_os << sp.first << ": ";
+            print_pattern(sp.second, is_refutable);
+            m_os << ",";
+        }
+        m_os << ")";
+        }),
+    (Tuple,
+        m_os << "(";
+        this->print_pattern_tuple(v, is_refutable);
+        m_os << ")";
+        ),
+    (Slice,
+        m_os << "[";
+        bool needs_comma = false;
+        if(v.leading.size()) {
+            m_os << v.leading;
+            needs_comma = true;
+        }
+        if(v.extra_bind.size() > 0) {
+            if( needs_comma ) {
+                m_os << ", ";
+            }
+            if(v.extra_bind != "_")
+                m_os << v.extra_bind;
+            m_os << "..";
+            needs_comma = true;
+        }
+        if(v.trailing.size()) {
+            if( needs_comma ) {
+                m_os << ", ";
+            }
+            m_os << v.trailing;
+        }
+        m_os << "]";
+        )
+    )
+}
+
+void RustPrinter::print_type(const TypeRef& t)
+{
+    m_os << t;
+}
+
+void RustPrinter::handle_struct(const AST::Struct& s)
+{
+    print_params(s.params());
+    
+    TU_MATCH(AST::StructData, (s.m_data), (e),
+    (Tuple,
+        if( e.ents.size() == 0 )
+        {
+            m_os << " /* unit-like */\n";
+            print_bounds(s.params());
+            m_os << indent() << ";\n";
+        }
+        else
+        {
+            m_os << "(";
+            for( const auto& i : e.ents )
+                m_os << i.m_type << ", ";
+            m_os << ")\n";
+            print_bounds(s.params());
+            m_os << indent() << ";\n";
+        }
+        ),
+    (Struct,
+        m_os << "\n";
+        print_bounds(s.params());
+        
+        m_os << indent() << "{\n";
+        inc_indent();
+        for( const auto& i : e.ents )
+        {
+            m_os << indent() << (i.m_is_public ? "pub " : "") << i.m_name << ": " << i.m_type.print_pretty() << "\n";
+        }
+        dec_indent();
+        m_os << indent() << "}\n";
+        )
+    )
+    m_os << "\n";
+}
+
+void RustPrinter::handle_enum(const AST::Enum& s)
+{
+    print_params(s.params());
+    m_os << "\n";
+    print_bounds(s.params());
+
+    m_os << indent() << "{\n";
+    inc_indent();
+    unsigned int idx = 0;
+    for( const auto& i : s.variants() )
+    {
+        m_os << indent() << "/*"<<idx<<"*/" << i.m_name;
+        TU_MATCH(AST::EnumVariantData, (i.m_data), (e),
+        (Value,
+            m_os << " = " << e.m_value;
+            ),
+        (Tuple,
+            m_os << "(";
+            for( const auto& t : e.m_sub_types )
+                m_os << t.print_pretty() << ", ";
+            m_os << ")";
+            ),
+        (Struct,
+            m_os << "{\n";
+            inc_indent();
+            for( const auto& i : e.m_fields )
+            {
+                m_os << indent() << i.m_name << ": " << i.m_type.print_pretty() << "\n";
+            }
+            dec_indent();
+            m_os << indent() << "}";
+            )
+        )
+        m_os << ",\n";
+        idx ++;
+    }
+    dec_indent();
+    m_os << indent() << "}\n";
+    m_os << "\n";
+}
+
+void RustPrinter::handle_trait(const AST::Trait& s)
+{
+    print_params(s.params());
+    m_os << "\n";
+    print_bounds(s.params());
+
+    m_os << indent() << "{\n";
+    inc_indent();
+    
+    for( const auto& i : s.items() )
+    {
+        TU_MATCH_DEF(AST::Item, (i.data), (e),
+        (
+            ),
+        (Type,
+            m_os << indent() << "type " << i.name << ";\n";
+            ),
+        (Function,
+            handle_function(false, i.name, e);
+            )
+        )
+    }
+    
+    dec_indent();
+    m_os << indent() << "}\n";
+    m_os << "\n";
+}
+
+void RustPrinter::handle_function(bool is_pub, const ::std::string& name, const AST::Function& f)
+{
+    m_os << indent();
+    m_os << (is_pub ? "pub " : "");
+    // TODO: Unsafe
+    // TODO: Const
+    m_os << "fn " << name;
+    print_params(f.params());
+    m_os << "(";
+    bool is_first = true;
+    for( const auto& a : f.args() )
+    {
+        if( !is_first )
+            m_os << ", ";
+        print_pattern( a.first, false );
+        m_os << ": " << a.second.print_pretty();
+        is_first = false;
+    }
+    m_os << ")";
+    if( !f.rettype().is_unit() )
+    {
+        m_os << " -> " << f.rettype().print_pretty();
+    }
+    
+    if( f.code().is_valid() )
+    {
+        m_os << "\n";
+        print_bounds(f.params());
+        
+        m_os << indent();
+        f.code().visit_nodes(*this);
+        m_os << "\n";
+        //m_os << indent() << f.data.code() << "\n";
+    }
+    else
+    {
+        print_bounds(f.params());
+        m_os << ";\n";
+    }
+}
+
+void RustPrinter::inc_indent()
+{
+    m_indent_level ++;
+}
+RepeatLitStr RustPrinter::indent()
+{
+    return RepeatLitStr { "    ", m_indent_level };
+}
+void RustPrinter::dec_indent()
+{
+    m_indent_level --;
+}