feat: enable_if

1 files changed, 20 insertions, 1 deletions

diff --git a/sfinae.y b/sfinae.y
index 1acb4d0..f97147f 100644
--- a/sfinae.y
+++ b/sfinae.y
@@ -23,6 +23,8 @@ void yyerror(const char* message);
 %token TOK_COMMIT
 %token TOK_DECLARE
 %token TOK_UNDECLARE
+%token TOK_ENABLE_IF
+%token TOK_SEQUENCE
 %token TOK_NAME
 %token TOK_VALUE_OF
 %token TOK_VOID
@@ -50,7 +52,7 @@ void yyerror(const char* message);
 %token <character> TOK_CHAR
 
 %type <name> name char_list
-%type <node> statements statement type value condition
+%type <node> statements statement sequence sequence_items type value condition
 
 %%
 
@@ -75,6 +77,23 @@ statement
         { $$ = node_named(STMT_DECLARE, &$4, $6); }
     | TOK_COLONCOLON TOK_UNDECLARE '<' name '>' TOK_COLONCOLON TOK_COMMIT
         { $$ = node_named(STMT_UNDECLARE, &$4, NULL); }
+    | TOK_COLONCOLON TOK_ENABLE_IF '<' condition ',' sequence '>' TOK_COLONCOLON TOK_COMMIT
+        { $$ = node_block(STMT_ENABLE_IF, $4, $6); }
+    ;
+
+// the statements inside are committed one by one, without the semicolons
+sequence
+    : TOK_COLONCOLON TOK_SEQUENCE '<' sequence_items '>'
+        { $$ = $4; }
+    ;
+
+sequence_items
+    : /* nothing */
+        { $$ = NULL; }
+    | statement
+        { $$ = $1; }
+    | sequence_items ',' statement
+        { $$ = node_append($1, $3); }
     ;
 
 name