diff --git a/include/xo/reader/expect_expr_xs.hpp b/include/xo/reader/expect_expr_xs.hpp index a7cc997f..fa6c4630 100644 --- a/include/xo/reader/expect_expr_xs.hpp +++ b/include/xo/reader/expect_expr_xs.hpp @@ -22,10 +22,20 @@ namespace xo { virtual void on_leftparen_token(const token_type & tk, exprstatestack * p_stack, rp * p_emit_expr) override; + + virtual void on_symbol_token(const token_type & tk, + exprstatestack * p_stack, + rp * p_emit_expr) override; + virtual void on_f64_token(const token_type & tk, exprstatestack * p_stack, rp * p_emit_expr) override; + /** update exprstate in response to a successfully-parsed subexpression **/ + virtual void on_expr(ref::brw expr, + exprstatestack * p_stack, + rp * p_emit_expr) override; + private: }; diff --git a/include/xo/reader/exprstate.hpp b/include/xo/reader/exprstate.hpp index 61ba3319..9f20dfd8 100644 --- a/include/xo/reader/exprstate.hpp +++ b/include/xo/reader/exprstate.hpp @@ -87,12 +87,6 @@ namespace xo { virtual bool admits_semicolon() const; /** true iff this parsing state admits a singleassign '=' as next token **/ virtual bool admits_singleassign() const; -#ifdef OBSOLETE - /** true iff this parsing state admits a leftparen '(' as next token **/ - virtual bool admits_leftparen() const; - /** truee iff this parsing state admits a rightparen ')' as next token **/ - virtual bool admits_rightparen() const; -#endif /** update exprstate in response to incoming token @p tk, * forward instructions to parent parser diff --git a/src/reader/expect_expr_xs.cpp b/src/reader/expect_expr_xs.cpp index be19b8bc..131bfc42 100644 --- a/src/reader/expect_expr_xs.cpp +++ b/src/reader/expect_expr_xs.cpp @@ -38,6 +38,41 @@ namespace xo { p_stack->push_exprstate(expect_expr_xs::expect_rhs_expression()); } + void + expect_expr_xs::on_symbol_token(const token_type & /*tk*/, + exprstatestack * /*p_stack*/, + rp * /*p_emit_expr*/) + { + /* todo: treat symbol as variable name */ + + /* various possibilities when looking for rhs expression: + * + * x := y // (1) + * x := f(a) // (2) + * x := f(a,b) // (3) + * + * need lookahead token following symbol to distinguish + * between (1) (symbol completes rhs expression) + * and {(2), (3)} (symbol is function call) + */ + + /* have to do pop first, before sending symbol to + * the o.g. symbol-requester + */ +#ifdef NOT_YET + p_stack->push_exprstate(exprstate(exprstatetype::expr_progress, + Variable::make(name, type))); +#endif + +#ifdef LATER + p_stack->pop_exprstate(); + p_stack->top_exprstate().on_symbol(tk.text(), + p_stack, p_emit_expr); +#endif + return; + } + + void expect_expr_xs::on_f64_token(const token_type & tk, exprstatestack * p_stack, @@ -57,6 +92,24 @@ namespace xo { (Constant::make(tk.f64_value()))); } + void + expect_expr_xs::on_expr(ref::brw expr, + exprstatestack * p_stack, + rp * p_emit_expr) + { + constexpr bool c_debug_flag = true; + scope log(XO_DEBUG(c_debug_flag)); + + log && log(xtag("exstype", this->exs_type_), + xtag("expr", expr)); + + + std::unique_ptr self = p_stack->pop_exprstate(); + + p_stack->top_exprstate().on_expr(expr, + p_stack, + p_emit_expr); + } /*on_expr*/ } /*namespace scm*/ } /*namespace xo*/ diff --git a/src/reader/exprstate.cpp b/src/reader/exprstate.cpp index 31553c1c..540bcaaa 100644 --- a/src/reader/exprstate.cpp +++ b/src/reader/exprstate.cpp @@ -50,14 +50,11 @@ namespace xo { case exprstatetype::defexpr: case exprstatetype::parenexpr: + case exprstatetype::expect_rhs_expression: /* unreachable */ assert(false); return false; - case exprstatetype::expect_rhs_expression: - /* treat symbol as variable name */ - return true; - case exprstatetype::expect_symbol: return true; @@ -179,40 +176,6 @@ namespace xo { return false; } -#ifdef OBSOLETE - bool - exprstate::admits_rightparen() const { - switch (exs_type_) { - case exprstatetype::expect_toplevel_expression_sequence: - return false; - - case exprstatetype::defexpr: - case exprstatetype::parenexpr: - /* unreachable - redirects to define_xs */ - assert(false); - return false; - - case exprstatetype::expect_rhs_expression: - return false; - - case exprstatetype::expect_type: - return false; - - case exprstatetype::expect_symbol: - return false; - - case exprstatetype::expr_progress: - case exprstatetype::invalid: - case exprstatetype::n_exprstatetype: - /* unreachable */ - assert(false); - return false; - } - - return false; - } -#endif - void exprstate::on_def_token(const token_type & tk, exprstatestack * /*p_stack*/) @@ -240,39 +203,11 @@ namespace xo { case exprstatetype::expect_toplevel_expression_sequence: case exprstatetype::defexpr: case exprstatetype::parenexpr: - /* unreachable - redirects to define_xs */ + case exprstatetype::expect_rhs_expression: + /* unreachable - redirected to define_xs etc */ assert(false); return; - case exprstatetype::expect_rhs_expression: - { - /* various possibilities when looking for rhs expression: - * - * x := y // (1) - * x := f(a) // (2) - * x := f(a,b) // (3) - * - * need lookahead token following symbol to distinguish - * between (1) (symbol completes rhs expression) - * and {(2), (3)} (symbol is function call) - */ - - /* have to do pop first, before sending symbol to - * the o.g. symbol-requester - */ -#ifdef NOT_YET - p_stack->push_exprstate(exprstate(exprstatetype::expr_progress, - Variable::make(name, type))); -#endif - -#ifdef LATER - p_stack->pop_exprstate(); - p_stack->top_exprstate().on_symbol(tk.text(), - p_stack, p_emit_expr); -#endif - return; - } - case exprstatetype::expect_symbol: { /* have to do pop first, before sending symbol to @@ -528,8 +463,8 @@ namespace xo { void exprstate::on_expr(ref::brw expr, - exprstatestack * p_stack, - rp * p_emit_expr) + exprstatestack * /*p_stack*/, + rp * /*p_emit_expr*/) { constexpr bool c_debug_flag = true; scope log(XO_DEBUG(c_debug_flag)); @@ -537,42 +472,7 @@ namespace xo { log && log(xtag("exstype", this->exs_type_), xtag("expr", expr)); - switch (this->exs_type_) { - case exprstatetype::expect_toplevel_expression_sequence: - case exprstatetype::defexpr: - case exprstatetype::parenexpr: - /* unreachable. redirects to define_xs::on_expr() etc */ - assert(false); - return; - - case exprstatetype::expect_rhs_expression: { - - std::unique_ptr self = p_stack->pop_exprstate(); - - p_stack->top_exprstate().on_expr(expr, - p_stack, - p_emit_expr); - - return; - } - - case exprstatetype::expect_type: - case exprstatetype::expect_symbol: - /* unreachable - * (this exprstate issues pop instruction from exprstate::on_input() - */ - assert(false); - return; - case exprstatetype::expr_progress: - /* unreachable */ - assert(false); - return; - case exprstatetype::invalid: - case exprstatetype::n_exprstatetype: - /* unreachable */ - assert(false); - return; - } + assert(false); } /*on_expr*/ void