roland/xo-alloc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

xo-reader: refactor: simplify define_xs behavior

Browse source
This commit is contained in:
Roland Conybeare 2024-08-18 23:29:36 -04:00
commit 818127a446
4 changed files with 110 additions and 181 deletions
Download patch file Download diff file Expand all files Collapse all files

61
include/xo/reader/define_xs.hpp
View file

@ -12,6 +12,36 @@
namespace xo {
namespace scm {
/**
* 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
*
**/
enum class defexprstatetype {
invalid = -1,
@ -21,6 +51,7 @@ namespace xo {
def_3,
def_4,
def_5,
def_6,
n_defexprstatetype,
};
@ -38,12 +69,13 @@ namespace xo {
virtual ~define_xs() = default;
static const define_xs * from(const exprstate * x) { return dynamic_cast<const define_xs *>(x); }
static std::unique_ptr<define_xs> def_0();
static void start(exprstatestack * p_stack);
defexprstatetype defxs_type() const { return defxs_type_; }
bool admits_rightparen() const;
bool admits_colon() const;
//bool admits_colon() const;
bool admits_semicolon() const;
//bool admits_symbol() const;
@ -58,6 +90,8 @@ namespace xo {
virtual void on_typedescr(TypeDescr td,
exprstatestack * p_stack,
rp<Expression> * p_emit_expr) override;
virtual void on_def_token(const token_type & tk,
exprstatestack * p_stack) override;
virtual void on_colon_token(const token_type & tk,
exprstatestack * p_stack) override;
virtual void on_semicolon_token(const token_type & tk,
@ -75,26 +109,9 @@ namespace xo {
virtual void print(std::ostream & os) const override;
private:
/**
* def foo : f64 = 1 ;
* ^ ^ ^ ^ ^ ^ ^ ^
* | | | | | | | (done)
* | | | | | | def_4:expect_rhs_expression:expr_progress
* | | | | | def_4:expect_rhs_expression
* | | | | def_3
* | | | def_2:expect_type
* | | def_1
* | def_0:expect_symbol
* expect_toplevel_expression_sequence
*
* def_0:expect_symbol: got 'def' keyword, symbol to follow
* def_1: got symbol name
* def_2:expect_symbol got (optional) colon, type name to follow
* def_3: got symbol type
* def_4:expect_rhs_expression got (optional) equal sign, value to follow
* (done): definition complete, pop exprstate from stack
*
**/
static std::unique_ptr<define_xs> make();
private:
defexprstatetype defxs_type_;
/** scaffold a define-expression here **/
rp<DefineExprAccess> def_expr_;