[erlang-questions] BNF/EBNF Grammar for Erlang

Kostis Sagonas <>
Sun Nov 13 18:40:08 CET 2011


On 11/13/11 19:26, Ryan Molden wrote:
>
> As an aside can you give me info/pointers on where to find info on the
> following terminals?
>
> ':-'   This seems to be used around 'rules' (which I have never seen in
> any Erlang program I have looked at, but I am a newb).  Examples or even
> just a name for this syntactic construct would be nice.  My lexer token
> currently calls it RULETHINGY :)
>
> '..'    Never seen this, but it is listed in the YRL file as a
> terminal.  Name and meaning would be nice.
>
> '...'   Never seen this, but it is listed in the YRL file as a
> terminal.  Name and meaning would be nice.

The last two are used in the language of type declarations that Erlang 
has.  The first is used to declare integer ranges, as in:

   -type small_int() :: 1..42.

and the second one to declare non-empty lists of some type, as in:

   -type sil() :: [small_int(),...].

Kostis



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