xo-expression2 xo-reader2: local symtab stack in PSM

xo-expression2/CMakeLists.txt

@@ -34,6 +34,30 @@ xo_add_genfacet(
 
 # ----------------------------------------------------------------
 
+xo_add_genfacetimpl(
+    TARGET xo-expression2-facetimpl-symboltable-localsymtab
+    FACET_PKG xo_expression2
+    FACET SymbolTable
+    REPR LocalSymtab
+    INPUT idl/ISymbolTable_DLocalSymtab.json5
+    OUTPUT_HPP_DIR include/xo/expression2
+    OUTPUT_IMPL_SUBDIR symtab
+    OUTPUT_CPP_DIR src/expression2
+)
+
+xo_add_genfacetimpl(
+    TARGET xo-expression2-facetimpl-printable-localsymtab
+    FACET_PKG xo_printable2
+    FACET Printable
+    REPR LocalSymtab
+    INPUT idl/IPrintable_DLocalSymtab.json5
+    OUTPUT_HPP_DIR include/xo/expression2
+    OUTPUT_IMPL_SUBDIR symtab
+    OUTPUT_CPP_DIR src/expression2
+)
+
+# ----------------------------------------------------------------
+
 # note: manual target; generated code committed to git
 xo_add_genfacet(
     TARGET xo-expression2-facet-expression

xo-expression2/idl/IPrintable_DLocalSymtab.json5

@@ -0,0 +1,13 @@
+{
+    mode: "implementation",
+    includes: [ "<xo/printable2/Printable.hpp>",
+                "<xo/printable2/detail/IPrintable_Xfer.hpp>" ],
+    local_types: [ ],
+    namespace1: "xo",
+    namespace2: "scm",
+    facet_idl: "idl/Printable.json5",
+    brief: "provide APrintable interface for DLocalSymtab",
+    using_doxygen: true,
+    repr: "DLocalSymtab",
+    doc: [ "implement APrintable for DLocalSymtab" ],
+}

xo-expression2/idl/ISymbolTable_DLocalSymtab.json5

@@ -0,0 +1,12 @@
+{
+    mode: "implementation",
+    includes: [ ],
+    local_types: [ ],
+    namespace1: "xo",
+    namespace2: "scm",
+    facet_idl: "idl/SymbolTable.json5",
+    brief: "provide ASymbolTable interface for DLocalSymtab",
+    using_doxygen: true,
+    repr: "DLocalSymtab",
+    doc: [ "implement ASymbolTable for DLocalSymtab" ],
+}

xo-expression2/include/xo/expression2/Binding.hpp

@@ -25,6 +25,7 @@ namespace xo {
             static Binding local(int32_t j_slot) { return Binding(0, j_slot); }
 
             bool is_global() const { return i_link_ == s_link_global; }
+            bool is_local() const { return (i_link_ == 0) && (j_slot_ >= 0); }
 
             int32_t i_link() const noexcept { return i_link_; }
             int32_t j_slot() const noexcept { return j_slot_; }

xo-expression2/include/xo/expression2/DLocalSymtab.hpp

@@ -45,20 +45,23 @@ namespace xo {
             /** @defgroup scm-lambdaexpr-constructors **/
             ///@{
 
-            /** empty instance with capacity for n slots.
+            /** empty instance with parent @p p and capacity for @p n slots.
              *  Caller must ensure that slots_[0..n) are actually addressable
              **/
-            DLocalSymtab(size_type n);
+            DLocalSymtab(DLocalSymtab * p, size_type n);
 
             /** scaffold empty symtab instance,
              *  with capacity for @p n slots, using memory from allocator @p mm
              **/
-            static DLocalSymtab * _make_empty(obj<AAllocator> mm, size_type n);
+            static DLocalSymtab * _make_empty(obj<AAllocator> mm,
+                                              DLocalSymtab * p,
+                                              size_type n);
 
             ///@}
             /** @defgroup scm-lambdaexpr-methods **/
             ///@{
 
+            DLocalSymtab * parent() const noexcept { return parent_; }
             size_type capacity() const noexcept { return capacity_; }
             size_type size() const noexcept { return size_; }
 
@@ -96,6 +99,8 @@ namespace xo {
             ///@}
 
         private:
+            /** parent symbol table from scoping surrounding this one **/
+            DLocalSymtab * parent_ = nullptr;
             /** actual range of slots_[] array.  Can use inices in [0,..,n) **/
             size_type capacity_ = 0;
             /** number of slots in use **/

xo-expression2/include/xo/expression2/detail/IExpression_DIfElseExpr.hpp

@@ -2,7 +2,7 @@
  *
  *  Generated automagically from ingredients:
  *  1. code generator:
- *       [/Users/roland/proj/xo-umbrella2/xo-facet/codegen/genfacet]
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
  *     arguments:
  *       --input [idl/IExpression_DIfElseExpr.json5]
  *  2. jinja2 template for abstract facet .hpp file:

xo-expression2/include/xo/expression2/detail/IGCObject_DVariable.hpp

@@ -2,7 +2,7 @@
  *
  *  Generated automagically from ingredients:
  *  1. code generator:
- *       [/Users/roland/proj/xo-umbrella2/xo-facet/codegen/genfacet]
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
  *     arguments:
  *       --input [idl/IGCObject_DVariable.json5]
  *  2. jinja2 template for abstract facet .hpp file:

xo-expression2/include/xo/expression2/detail/IPrintable_DIfElseExpr.hpp

@@ -2,7 +2,7 @@
  *
  *  Generated automagically from ingredients:
  *  1. code generator:
- *       [/Users/roland/proj/xo-umbrella2/xo-facet/codegen/genfacet]
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
  *     arguments:
  *       --input [idl/IPrintable_DIfElseExpr.json5]
  *  2. jinja2 template for abstract facet .hpp file:

xo-expression2/include/xo/expression2/symtab/IPrintable_DLocalSymtab.hpp

@@ -0,0 +1,62 @@
+/** @file IPrintable_DLocalSymtab.hpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/IPrintable_DLocalSymtab.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_repr.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/IPrintable_DLocalSymtab.json5]
+ **/
+
+#pragma once
+
+#include "Printable.hpp"
+#include <xo/printable2/Printable.hpp>
+#include <xo/printable2/detail/IPrintable_Xfer.hpp>
+#include "DLocalSymtab.hpp"
+
+namespace xo { namespace scm { class IPrintable_DLocalSymtab; } }
+
+namespace xo {
+    namespace facet {
+        template <>
+        struct FacetImplementation<xo::print::APrintable,
+                                   xo::scm::DLocalSymtab>
+        {
+            using ImplType = xo::print::IPrintable_Xfer
+              <xo::scm::DLocalSymtab,
+               xo::scm::IPrintable_DLocalSymtab>;
+        };
+    }
+}
+
+namespace xo {
+    namespace scm {
+        /** @class IPrintable_DLocalSymtab
+         **/
+        class IPrintable_DLocalSymtab {
+        public:
+            /** @defgroup scm-printable-dlocalsymtab-type-traits **/
+            ///@{
+            using ppindentinfo = xo::print::APrintable::ppindentinfo;
+            using Copaque = xo::print::APrintable::Copaque;
+            using Opaque = xo::print::APrintable::Opaque;
+            ///@}
+            /** @defgroup scm-printable-dlocalsymtab-methods **/
+            ///@{
+            // const methods
+            /** Pretty-printing support for this object.
+See [xo-indentlog/xo/indentlog/pretty.hpp] **/
+            static bool pretty(const DLocalSymtab & self, const ppindentinfo & ppii);
+
+            // non-const methods
+            ///@}
+        };
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end */

xo-expression2/include/xo/expression2/symtab/ISymbolTable_DLocalSymtab.hpp

@@ -0,0 +1,60 @@
+/** @file ISymbolTable_DLocalSymtab.hpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/ISymbolTable_DLocalSymtab.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_repr.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/ISymbolTable_DLocalSymtab.json5]
+ **/
+
+#pragma once
+
+#include "SymbolTable.hpp"
+#include "DLocalSymtab.hpp"
+
+namespace xo { namespace scm { class ISymbolTable_DLocalSymtab; } }
+
+namespace xo {
+    namespace facet {
+        template <>
+        struct FacetImplementation<xo::scm::ASymbolTable,
+                                   xo::scm::DLocalSymtab>
+        {
+            using ImplType = xo::scm::ISymbolTable_Xfer
+              <xo::scm::DLocalSymtab,
+               xo::scm::ISymbolTable_DLocalSymtab>;
+        };
+    }
+}
+
+namespace xo {
+    namespace scm {
+        /** @class ISymbolTable_DLocalSymtab
+         **/
+        class ISymbolTable_DLocalSymtab {
+        public:
+            /** @defgroup scm-symboltable-dlocalsymtab-type-traits **/
+            ///@{
+            using Copaque = xo::scm::ASymbolTable::Copaque;
+            using Opaque = xo::scm::ASymbolTable::Opaque;
+            ///@}
+            /** @defgroup scm-symboltable-dlocalsymtab-methods **/
+            ///@{
+            // const methods
+            /** true iff this is toplevel (global) symbol table. **/
+            static bool is_global_symtab(const DLocalSymtab & self) noexcept;
+            /** report ingredients needed to address variable at runtime. **/
+            static Binding lookup_binding(const DLocalSymtab & self, const DUniqueString * sym) noexcept;
+
+            // non-const methods
+            ///@}
+        };
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end */

xo-expression2/src/expression2/CMakeLists.txt

@@ -39,6 +39,9 @@ set(SELF_SRCS
 
     ISymbolTable_Any.cpp
 
+    ISymbolTable_DLocalSymtab.cpp
+    IPrintable_DLocalSymtab.cpp
+
     StringTable.cpp
 
     DUniqueString.cpp

xo-expression2/src/expression2/DLocalSymtab.cpp

@@ -5,14 +5,21 @@
 
 #include "DLocalSymtab.hpp"
 #include "DUniqueString.hpp"
+#include <xo/expression2/detail/IPrintable_DVariable.hpp>
+#include <xo/printable2/Printable.hpp>
 #include <xo/indentlog/scope.hpp>
 
 namespace xo {
+    using xo::print::APrintable;
     using xo::facet::typeseq;
+    using xo::print::ppstate;
 
     namespace scm {
 
-        DLocalSymtab::DLocalSymtab(size_type n) : capacity_{n}, size_{0}
+        DLocalSymtab::DLocalSymtab(DLocalSymtab * p,
+                                   size_type n) : parent_{p},
+                                                  capacity_{n},
+                                                  size_{0}
         {
             for (size_type i = 0; i < n; ++i) {
                 void * mem = &slots_[i];
@@ -21,12 +28,14 @@ namespace xo {
         }
 
         DLocalSymtab *
-        DLocalSymtab::_make_empty(obj<AAllocator> mm, size_type n)
+        DLocalSymtab::_make_empty(obj<AAllocator> mm,
+                                  DLocalSymtab * p,
+                                  size_type n)
         {
             void * mem = mm.alloc(typeseq::id<DLocalSymtab>(),
                                   sizeof(DLocalSymtab) + (n * sizeof(Slot)));
 
-            return new (mem) DLocalSymtab(n);
+            return new (mem) DLocalSymtab(p, n);
         }
 
         Binding
@@ -68,6 +77,53 @@ namespace xo {
             return Binding();
         }
 
+        bool
+        DLocalSymtab::pretty(const ppindentinfo & ppii) const
+        {
+            ppstate * pps = ppii.pps();
+
+            if (ppii.upto()) {
+                /* perhaps print on one line */
+                if (!pps->print_upto("<LocalSymtab"))
+                    return false;
+                if (!pps->print_upto(xrefrtag("size", size_)))
+                    return false;
+
+                for (size_type i = 0; i < size_; ++i) {
+                    char buf[32];
+                    snprintf(buf, sizeof(buf), "[%u]", i);
+
+                    assert(slots_[i].var_);
+
+                    obj<APrintable,DVariable> arg_pr(const_cast<DVariable*>(slots_[i].var_));
+
+                    if (!pps->print_upto(xrefrtag(buf, arg_pr)))
+                        return false;
+                }
+
+                pps->write(">");
+                return true;
+            } else {
+                /* with line breaks */
+
+                pps->write("<LocalSymtab");
+                pps->newline_pretty_tag(ppii.ci1(), "size", size_);
+
+                for (size_type i = 0; i < size_; ++i) {
+                    char buf[32];
+                    snprintf(buf, sizeof(buf), "[%u]", i);
+
+                    assert(slots_[i].var_);
+
+                    obj<APrintable,DVariable> arg_pr(const_cast<DVariable *>(slots_[i].var_));
+
+                    pps->newline_pretty_tag(ppii.ci1(), buf, arg_pr);
+                }
+
+                pps->write(">");
+                return false;
+            }
+        }
     } /*namespace scm*/
 } /*namespace xo*/
 

xo-expression2/src/expression2/IExpression_DIfElseExpr.cpp

@@ -2,7 +2,7 @@
  *
  *  Generated automagically from ingredients:
  *  1. code generator:
- *       [/Users/roland/proj/xo-umbrella2/xo-facet/codegen/genfacet]
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
  *     arguments:
  *       --input [idl/IExpression_DIfElseExpr.json5]
  *  2. jinja2 template for abstract facet .hpp file:

xo-expression2/src/expression2/IGCObject_DVariable.cpp

@@ -2,7 +2,7 @@
  *
  *  Generated automagically from ingredients:
  *  1. code generator:
- *       [/Users/roland/proj/xo-umbrella2/xo-facet/codegen/genfacet]
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
  *     arguments:
  *       --input [idl/IGCObject_DVariable.json5]
  *  2. jinja2 template for abstract facet .hpp file:

xo-expression2/src/expression2/IPrintable_DIfElseExpr.cpp

@@ -2,7 +2,7 @@
  *
  *  Generated automagically from ingredients:
  *  1. code generator:
- *       [/Users/roland/proj/xo-umbrella2/xo-facet/codegen/genfacet]
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
  *     arguments:
  *       --input [idl/IPrintable_DIfElseExpr.json5]
  *  2. jinja2 template for abstract facet .hpp file:

xo-expression2/src/expression2/IPrintable_DLocalSymtab.cpp

@@ -0,0 +1,28 @@
+/** @file IPrintable_DLocalSymtab.cpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/IPrintable_DLocalSymtab.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_any.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/IPrintable_DLocalSymtab.json5]
+**/
+
+#include "symtab/IPrintable_DLocalSymtab.hpp"
+
+namespace xo {
+    namespace scm {
+        auto
+        IPrintable_DLocalSymtab::pretty(const DLocalSymtab & self, const ppindentinfo & ppii) -> bool
+        {
+            return self.pretty(ppii);
+        }
+
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end IPrintable_DLocalSymtab.cpp */

xo-expression2/src/expression2/ISymbolTable_DLocalSymtab.cpp

@@ -0,0 +1,34 @@
+/** @file ISymbolTable_DLocalSymtab.cpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [/home/roland/proj/xo-umbrella2-claude1/xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/ISymbolTable_DLocalSymtab.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_any.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/ISymbolTable_DLocalSymtab.json5]
+**/
+
+#include "symtab/ISymbolTable_DLocalSymtab.hpp"
+
+namespace xo {
+    namespace scm {
+        auto
+        ISymbolTable_DLocalSymtab::is_global_symtab(const DLocalSymtab & self) noexcept -> bool
+        {
+            return self.is_global_symtab();
+        }
+
+        auto
+        ISymbolTable_DLocalSymtab::lookup_binding(const DLocalSymtab & self, const DUniqueString * sym) noexcept -> Binding
+        {
+            return self.lookup_binding(sym);
+        }
+
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end ISymbolTable_DLocalSymtab.cpp */

xo-expression2/src/expression2/expression2_register_facets.cpp

@@ -27,6 +27,9 @@
 #include <xo/expression2/detail/IExpression_DIfElseExpr.hpp>
 #include <xo/expression2/detail/IPrintable_DIfElseExpr.hpp>
 
+#include <xo/expression2/symtab/ISymbolTable_DLocalSymtab.hpp>
+#include <xo/expression2/symtab/IPrintable_DLocalSymtab.hpp>
+
 #include <xo/gc/detail/AGCObject.hpp>
 #include <xo/printable2/detail/APrintable.hpp>
 #include <xo/facet/FacetRegistry.hpp>
@@ -74,6 +77,9 @@ namespace xo {
             FacetRegistry::register_impl<AExpression, DIfElseExpr>();
             FacetRegistry::register_impl<APrintable, DIfElseExpr>();
 
+            FacetRegistry::register_impl<ASymbolTable, DLocalSymtab>();
+            FacetRegistry::register_impl<APrintable, DLocalSymtab>();
+
             log && log(xtag("DUniqueString.tseq", typeseq::id<DUniqueString>()));
             log && log(xtag("DDefineExpr.tseq", typeseq::id<DDefineExpr>()));
             log && log(xtag("DVariable.tseq", typeseq::id<DVariable>()));
@@ -82,7 +88,10 @@ namespace xo {
             log && log(xtag("DLambdaExpr.tseq", typeseq::id<DLambdaExpr>()));
             log && log(xtag("DIfElseExpr.tseq", typeseq::id<DIfElseExpr>()));
 
+            log && log(xtag("DLocalSymtab.tseq", typeseq::id<DLocalSymtab>()));
+
             log && log(xtag("AExpression.tqseq", typeseq::id<AExpression>()));
+            log && log(xtag("ASymbolTable.tseq", typeseq::id<ASymbolTable>()));
 
             return true;
         }

xo-reader2/include/xo/reader2/DExpectFormalArglistSsm.hpp

@@ -71,14 +71,18 @@ namespace xo {
             /** @defgroup scm-expectformalarglistssm-methods general methods **/
             ///@{
 
-            /** update state on incoming token @p tk, with overall parser state in @p psm **/
+            /** update state on incoming token @p tk, with overall parser state in @p p_psm **/
             void on_leftparen_token(const Token & tk,
                                     ParserStateMachine * p_psm);
 
-            /** update state on incoming token @p tk, with overall parser state in @p psm **/
+            /** update state on incoming token @p tk, with overall parser state in @p p_psm **/
             void on_comma_token(const Token & tk,
                                 ParserStateMachine * p_psm);
 
+            /** update state on incoming rightparen token @p tk, with overall parser state in @p p_psm **/
+            void on_rightparen_token(const Token & tk,
+                                     ParserStateMachine * p_psm);
+
             ///@}
             /** @defgroup scm-expectformalarglistssm-ssm-facet syntaxstatemachine facet methods **/
             ///@{

xo-reader2/include/xo/reader2/DLambdaSsm.hpp

@@ -144,8 +144,6 @@ namespace xo {
 #ifdef NOT_YET
             virtual const char * get_expect_str() const override;
 
-            virtual void on_formal_arglist(const std::vector<rp<Variable>> & argl,
-                                           parserstatemachine * p_psm) override;
             virtual void on_leftbrace_token(const token_type & tk,
                                             parserstatemachine * p_psm) override;
             virtual void on_colon_token(const token_type & tk,
@@ -173,10 +171,10 @@ namespace xo {
             /** parsing state-machine state **/
             lambdastatetype lmstate_ = lambdastatetype::lm_0;
 
-#ifdef NOT_YET
             /** lambda environment (for formal parameters) **/
             DLocalSymtab * local_symtab_ = nullptr;
 
+#ifdef NOT_YET
             /** explicit return type (if supplied) **/
             TypeDescr explicit_return_td_ = nullptr;
 

xo-reader2/include/xo/reader2/ParserStateMachine.hpp

@@ -6,6 +6,8 @@
 #pragma once
 
 #include "ParserResult.hpp"
+#include <xo/expression2/DGlobalSymtab.hpp>
+#include <xo/expression2/DLocalSymtab.hpp>
 #include <xo/expression2/DVariable.hpp>
 #include <xo/expression2/StringTable.hpp>
 #include <xo/tokenizer2/Token.hpp>
@@ -47,6 +49,7 @@ namespace xo {
             bool debug_flag() const noexcept { return debug_flag_; }
             ParserStack * stack() const noexcept { return stack_; }
             obj<AAllocator> expr_alloc() const noexcept { return expr_alloc_; }
+            DLocalSymtab * local_symtab() const noexcept { return local_symtab_; }
             const ParserResult & result() const noexcept { return result_; }
 
             /** true iff state machine is currently idle (at top-level) **/
@@ -79,6 +82,15 @@ namespace xo {
              **/
             const DUniqueString * intern_string(std::string_view str);
 
+            /** push nested local symtab while parsing the body of a lambda expression;
+             *  restore previous symtab at the end of lambda-expression definition.
+             *  See @ref pop_local_symtab
+             **/
+            void push_local_symtab(DLocalSymtab * symtab);
+
+            /** pop nested symbol table from symbol-table stack **/
+            void pop_local_symtab();
+
             /** add variable to current local environment (innermost lexical scope) **/
             void upsert_var(DVariable * var);
 
@@ -219,8 +231,10 @@ namespace xo {
              *  after encountering a parsing error.
              **/
             DArena::Checkpoint parser_alloc_ckp_;
-
+            /** parser stack. Memory always from @ref parser_alloc_;
-            /** parser stack. Memory from @ref parser_alloc_ **/
+             *  elements that should survive parsing allocate from
+             *  @ref expr_alloc_, see below.
+             **/
             ParserStack * stack_ = nullptr;
 
             /** Allocator for parsed expressions.
@@ -239,6 +253,19 @@ namespace xo {
              **/
             obj<AAllocator> expr_alloc_;
 
+            /** symbol table with local bindings.
+             *  non-null during parsing of lambda expressions.
+             *  Always allocated from @p expr_alloc_.
+             *  Push local symbol table here to remember local params
+             *  during the body of a lambda expression.
+             **/
+            DLocalSymtab * local_symtab_ = nullptr;
+
+            /** global symbol table.
+             *  Toplevel definitions go here.
+             **/
+            DGlobalSymtab * global_symtab_ = nullptr;
+
             /** current output from parser **/
             ParserResult result_;
 

xo-reader2/src/reader2/DExpectFormalArglistSsm.cpp

@@ -126,6 +126,10 @@ namespace xo {
                 this->on_comma_token(tk, p_psm);
                 return;
 
+            case tokentype::tk_rightparen:
+                this->on_rightparen_token(tk, p_psm);
+                return;
+
                 // all the not-yet-handled cases
             case tokentype::tk_lambda:
             case tokentype::tk_def:
@@ -139,7 +143,6 @@ namespace xo {
             case tokentype::tk_bool:
             case tokentype::tk_semicolon:
             case tokentype::tk_invalid:
-            case tokentype::tk_rightparen:
             case tokentype::tk_leftbracket:
             case tokentype::tk_rightbracket:
             case tokentype::tk_leftbrace:
@@ -300,20 +303,22 @@ namespace xo {
                                           this->get_expect_str());
         }
 
-#ifdef NOT_YET
         void
-        expect_formal_arglist_xs::on_rightparen_token(const token_type & tk,
+        DExpectFormalArglistSsm::on_rightparen_token(const Token & tk,
-                                                      parserstatemachine * p_psm)
+                                                     ParserStateMachine * p_psm)
         {
-            if (farglxs_type_ == formalarglstatetype::argl_1b) {
+            if (fastate_ == formalarglstatetype::argl_1b) {
-                std::unique_ptr<exprstate> self = p_psm->pop_exprstate();
+                DArray * args = argl_;
 
-                p_psm->top_exprstate().on_formal_arglist(this->argl_, p_psm);
+                p_psm->pop_ssm();
-            } else {
+                p_psm->on_parsed_formal_arglist(args);
-                exprstate::on_rightparen_token(tk, p_psm);
+                return;
             }
+
+            p_psm->illegal_input_on_token("DExpectFormalArglistSsm::on_rightparen_token",
+                                          tk,
+                                          this->get_expect_str());
         }
-#endif
 
         bool
         DExpectFormalArglistSsm::pretty(const ppindentinfo & ppii) const

xo-reader2/src/reader2/DLambdaSsm.cpp

@@ -9,6 +9,9 @@
 #include "ssm/ISyntaxStateMachine_DExpectFormalArglistSsm.hpp"
 #include "ParserStateMachine.hpp"
 #include "syntaxstatetype.hpp"
+#include <xo/expression2/DVariable.hpp>
+#include <xo/expression2/detail/IExpression_DVariable.hpp>
+//#include <xo/expression2/symtab/ISymbolTable_DLocalSymtab.hpp>
 #include <xo/printable2/Printable.hpp>
 #include <xo/facet/FacetRegistry.hpp>
 #include <xo/arena/DArena.hpp>
@@ -28,6 +31,7 @@
 namespace xo {
     using xo::print::APrintable;
     using xo::mm::AAllocator;
+    using xo::mm::AGCObject;
     using xo::facet::FacetRegistry;
     using xo::reflect::typeseq;
 
@@ -353,6 +357,54 @@ namespace xo {
         DLambdaSsm::on_parsed_formal_arglist(DArray * arglist,
                                              ParserStateMachine * p_psm)
         {
+            if (lmstate_ == lambdastatetype::lm_1) {
+                this->lmstate_ = lambdastatetype::lm_2;
+                /// something with top env frame ?
+
+                /// TODO: arena-friendly non-gc-aware vector;
+                //        use instead of DArray for arglist.
+                //        something like DTypedArray<T>
+
+                /// create LocalSymtab from arglist
+
+                DLocalSymtab * symtab
+                    = DLocalSymtab::_make_empty(p_psm->expr_alloc(),
+                                                p_psm->local_symtab(),
+                                                arglist->size());
+                assert(symtab);
+
+                for (DArray::size_type i = 0, n = arglist->size(); i < n; ++i) {
+                    obj<AGCObject> param = arglist->at(i);
+
+                    // sad! runtime poly conversion from obj<AGCObject>
+                    // We on need this because of (suboptimally) using DArray to store arglist
+
+                    obj<AExpression> param_expr
+                        = FacetRegistry::instance().variant<AExpression,AGCObject>(param);
+                    obj<AExpression,DVariable> param_var
+                        = obj<AExpression,DVariable>::from(param_expr);
+
+                    assert(param_expr.data());
+                    assert(param_var.data());
+
+                    Binding b = symtab->append_var(p_psm->expr_alloc(),
+                                                   param_var.data()->name(),
+                                                   param_var.data()->typeref());
+
+                    assert(b.is_local());
+
+                    this->local_symtab_ = symtab;
+                }
+
+                // stash env frame: records local variables while we handle lambda body
+
+                p_psm->push_local_symtab(symtab);
+
+                // control reenters via .on_colon_token() / .on_leftbrace_token()
+
+                return;
+            }
+
             p_psm->illegal_parsed_formal_arglist("DLambdaSsm::on_parsed_formal_arglist",
                                                  arglist,
                                                  this->get_expect_str());

xo-reader2/src/reader2/ParserStack.cpp

@@ -70,7 +70,7 @@ namespace xo {
             std::size_t i_frame = 0;
 
             while (frame) {
-                char buf[80];
+                char buf[32];
                 snprintf(buf, sizeof(buf), "[%lu]", i_frame);
 
                 auto ssm = (FacetRegistry::instance().variant

xo-reader2/src/reader2/ParserStateMachine.cpp

@@ -88,6 +88,20 @@ namespace xo {
             return stringtable_.intern(str);
         }
 
+        void
+        ParserStateMachine::push_local_symtab(DLocalSymtab * symtab)
+        {
+            this->local_symtab_ = symtab;
+        }
+
+        void
+        ParserStateMachine::pop_local_symtab()
+        {
+            assert(local_symtab_);
+
+            this->local_symtab_ = local_symtab_->parent();
+        }
+
         void
         ParserStateMachine::upsert_var(DVariable * var)
         {
@@ -310,6 +324,12 @@ namespace xo {
                                        xtag("expecting", expect_str),
                                        xtag("ssm", ssm_name),
                                        xtag("via", "ParserStateMachine::illegal_parsed_formal_arglist"));
+
+            assert(expr_alloc_);
+
+            auto errmsg = DString::from_str(expr_alloc_, errmsg_string);
+
+            this->capture_error(ssm_name, errmsg);
         }
 
         void

xo-reader2/utest/SchematikaParser.test.cpp

@@ -327,11 +327,10 @@ namespace xo {
                 REQUIRE(result.is_incomplete());
             }
 
-#ifdef NOT_YET
             {
-                auto & result = parser.on_token(Token::else_token());
+                auto & result = parser.on_token(Token::rightparen_token());
 
-                log && log("after else token:");
+                log && log("after rightparen token:");
                 log && log(xtag("parser", &parser));
                 log && log(xtag("result", result));
 
@@ -340,6 +339,7 @@ namespace xo {
                 REQUIRE(result.is_incomplete());
             }
 
+#ifdef NOT_YET
             {
                 auto & result = parser.on_token(Token::string_token("fooey"));
 

xo-tokenizer2/include/xo/tokenizer2/Token.hpp

@@ -94,7 +94,7 @@ namespace xo {
             /** token representing left parenthesis @c "(" **/
             static Token leftparen_token() { return Token(tokentype::tk_leftparen); }
             /** Token representing right parenthesis @c ")" **/
-            static Token rightparen() { return Token(tokentype::tk_rightparen); }
+            static Token rightparen_token() { return Token(tokentype::tk_rightparen); }
             /** token representing left bracket @c "[" **/
             static Token leftbracket() { return Token(tokentype::tk_leftbracket); }
             /** token representing right bracket @c "]" **/