-of mixfix operators like \id{if_then_else_} as a way to add new +of mixfix operators like \id{if_then_else} as a way to add new
No, no: the identifier is \id{if_then_else_} because there's something after the "else".
+\subsection{Nemerle} +% \TODO{ Actually, in Typer we currently can't add new syntax, and +% there's no reason why it should be strictly linked to the definition +% of new macros. } +% Vincent : In Typer if_then_else and for_each can be added as macros (or functions) +% with operators. This is what I mean by new syntax.
We can define
if_then_else = macro (lambda ...);
but that will only let the user write
if_then_else E1 E2 E3
rather than
if E1 then E2 else E3
so we do not currently support the equivalent of Nemerle's `Syntax` (although we do intend to add that kind of functionality and all it takes is to adjust the parser's precedence tables at the right place).
Stefan