feat: add bison grammar for emit, decltype and difference

1 files changed, 64 insertions, 0 deletions

diff --git a/sfinae.y b/sfinae.y
new file mode 100644
index 0000000..2e91b23
--- /dev/null
+++ b/sfinae.y
@@ -0,0 +1,64 @@
+%{
+#include "ast.h"
+#include "lexer.h"
+
+#include <stdio.h>
+
+struct Node* program_root = NULL;
+
+void yyerror(const char* message);
+%}
+
+%union
+{
+    char character;
+    struct Node* node;
+}
+
+%token TOK_COLONCOLON
+%token TOK_EMIT
+%token TOK_COMMIT
+%token TOK_DECLTYPE
+%token TOK_DIFFERENCE
+%token <character> TOK_CHAR
+
+%type <node> statements statement type value
+
+%%
+
+program
+    : statements
+        { program_root = $1; }
+    ;
+
+statements
+    : /* nothing */
+        { $$ = NULL; }
+    | statements statement ';'
+        { $$ = node_append($1, $2); }
+    ;
+
+statement
+    : TOK_COLONCOLON TOK_EMIT '<' type '>' TOK_COLONCOLON TOK_COMMIT
+        { $$ = node_unary(STMT_EMIT, $4); }
+    ;
+
+type
+    : TOK_COLONCOLON TOK_DECLTYPE '(' value ')'
+        { $$ = node_unary(TYPE_DECLTYPE, $4); }
+    ;
+
+value
+    : TOK_COLONCOLON TOK_DIFFERENCE '<' TOK_CHAR ',' TOK_CHAR '>'
+        { $$ = node_binary(VALUE_DIFFERENCE, node_char($4), node_char($6)); }
+    ;
+
+%%
+
+void yyerror(const char* message)
+{
+    if (!lexer_failed())
+    {
+        (void)fprintf(stderr, "line %d: %s, did you forget to commit\n", yylineno, message);
+    }
+}