xo-reader2: + DDefineSsm + utest

include/xo/reader2/DDefineSsm.hpp

@@ -0,0 +1,97 @@
+/** @file DDefineSsm.hpp
+ *
+ *  @author Roland Conybeare, Jan 2026
+ **/
+
+#include "ParserStateMachine.hpp"
+#include "SyntaxStateMachine.hpp"
+#include "syntaxstatetype.hpp"
+#include <xo/facet/obj.hpp>
+
+namespace xo {
+    namespace scm {
+        /**
+         * @pre
+         *
+         *   def foo : f64 = 1 ;
+         *  ^   ^   ^ ^   ^ ^ ^ ^
+         *  |   |   | |   | | | (done)
+         *  |   |   | |   | | def_6:expect_rhs_expression:expr_progress
+         *  |   |   | |   | def_5:expect_rhs_expression
+         *  |   |   | |   def_4
+         *  |   |   | def_3:expect_type
+         *  |   |   def_2
+         *  |   def_1:expect_symbol
+         *  def_0
+         *  expect_toplevel_expression_sequence
+         *
+         *   def_0 --on_def_token()--> def_1
+         *   def_1 --on_symbol()--> def_2
+         *   def_2 --on_colon_token()--> def_3
+         *         --on_singleassign_token()--> def_5
+         *   def_3 --on_typedescr()--> def_4
+         *   def_4 --on_singleassign_token()--> def_5
+         *   def_5 --on_expr()--> def_6
+         *   def_6 --on_semicolon_token()--> (done)
+         *
+         *   def_1:expect_symbol: got 'def' keyword, symbol to follow
+         *   def_1: got symbol name
+         *   def_3:expect_symbol got (optional) colon, type name to follow
+         *   def_4: got symbol type
+         *   def_6:expect_rhs_expression got (optional) equal sign, value to follow
+         *   (done): definition complete,  pop exprstate from stack
+         *
+         * @endpre
+         **/
+        enum class defexprstatetype {
+            invalid = -1,
+
+            def_0,
+            def_1,
+            def_2,
+            def_3,
+            def_4,
+            def_5,
+            def_6,
+
+            n_defexprstatetype,
+        };
+
+        extern const char * defexprstatetype_descr(defexprstatetype x);
+
+        std::ostream &
+        operator<<(std::ostream & os, defexprstatetype x);
+
+        /** @class DDefineSsm
+         *  @brief state machine for parsing a define expression
+         **/
+        class DDefineSsm {
+        public:
+
+        public:
+            /** @defgroup scm-define-ssm-facet syntaxstatemachine facet methods **/
+            ///@{
+
+            /** identifies the ssm implemented here **/
+            syntaxstatetype ssm_type() const noexcept;
+
+            /** text describing expected/allowed input to this ssm in current state.
+             *  Intended to drive error mesages
+             **/
+            std::string_view get_expect_str() const noexcept;
+
+            /** update state for this syntax on incoming token @p tk,
+             *  overall parser state in @p p_psm
+             **/
+            void on_if_token(const Token & tk, ParserStateMachine * p_psm);
+
+            ///@}
+
+        private:
+            /** identify define-expression state **/
+            defexprstatetype defstate_;
+        };
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end DDefineSsm.hpp */

include/xo/reader2/SchematikaParser.hpp

@@ -198,7 +198,7 @@ namespace xo {
              *  @return parsed expression, if @p tk completes an expression.
              *  otherwise nullptr
              **/
-            const ParserResult & include_token(const token_type & tk);
+            const ParserResult & on_token(const token_type & tk);
 
             /** reset parsed result expression; use using return value from
              *  @ref include_token. Complicating api here to avoid copying ParserResult

include/xo/reader2/ssm/ISyntaxStateMachine_DDefineSsm.hpp

@@ -0,0 +1,66 @@
+/** @file ISyntaxStateMachine_DDefineSsm.hpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [/Users/roland/proj/xo-umbrella2/xo-facet/codegen/genfacet]
+ *     arguments:
+ *       --input [idl/ISyntaxStateMachine_DDefineSsm.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [iface_facet_repr.hpp.j2]
+ *  3. idl for facet methods
+ *       [idl/ISyntaxStateMachine_DDefineSsm.json5]
+ **/
+
+#pragma once
+
+#include "SyntaxStateMachine.hpp"
+#include "SyntaxStateMachine.hpp"
+#include "ssm/ISyntaxStateMachine_Xfer.hpp"
+#include "DDefineSsm.hpp"
+
+namespace xo { namespace scm { class ISyntaxStateMachine_DDefineSsm; } }
+
+namespace xo {
+    namespace facet {
+        template <>
+        struct FacetImplementation<xo::scm::ASyntaxStateMachine,
+                                   xo::scm::DDefineSsm>
+        {
+            using ImplType = xo::scm::ISyntaxStateMachine_Xfer
+              <xo::scm::DDefineSsm,
+               xo::scm::ISyntaxStateMachine_DDefineSsm>;
+        };
+    }
+}
+
+namespace xo {
+    namespace scm {
+        /** @class ISyntaxStateMachine_DDefineSsm
+         **/
+        class ISyntaxStateMachine_DDefineSsm {
+        public:
+            /** @defgroup scm-syntaxstatemachine-ddefinessm-type-traits **/
+            ///@{
+            using Copaque = xo::scm::ASyntaxStateMachine::Copaque;
+            using Opaque = xo::scm::ASyntaxStateMachine::Opaque;
+            ///@}
+            /** @defgroup scm-syntaxstatemachine-ddefinessm-methods **/
+            ///@{
+            // const methods
+            /** identify a type of syntax state machine **/
+            static syntaxstatetype ssm_type(const DDefineSsm & self) noexcept;
+            /** text describing expected/allowed input to this ssm in current state **/
+            static std::string_view get_expect_str(const DDefineSsm & self) noexcept;
+
+            // non-const methods
+            /** update state machine for incoming define-keyworkd-token @p tk **/
+            static void on_def_token(DDefineSsm & self, const Token & tk, ParserStateMachine * ps_psm);
+            /** update state machine for incoming if-keyword-token @p tk **/
+            static void on_if_token(DDefineSsm & self, const Token & tk, ParserStateMachine * p_psm);
+            ///@}
+        };
+
+    } /*namespace scm*/
+} /*namespace xo*/
+
+/* end */

include/xo/reader2/syntaxstatetype.hpp

@@ -21,6 +21,9 @@ namespace xo {
             /** toplevel of some translation unit. See @ref DExprSeqState **/
             expect_toplevel_expression_sequence,
 
+            /** handle define-expression. See @ref DDefineSsm **/
+            defexpr,
+
             /** comes lasts, counts number of valid enums **/
             N
         };