[erlang-questions] spec declaration for single list parameter with fixed size

Michael Richter ttmrichter@REDACTED
Sun Jul 3 11:58:34 CEST 2011

On 3 July 2011 16:10, Roberto Ostinelli <roberto@REDACTED> wrote:

> a very stupid spec declaration question. how can you declare the specs of a
> function which has a single list with multiple arguments?
For instance, consider this function:

> myfun([One, Two]) ->

> these two following declarations do obviously not work:
> -spec myfun([One::string(), Two::integer()]) ->
> -spec myfun(list(One::string(), Two::integer())) ->

> the proper way seems to be:
> -spec myfun([string() | integer()]) ->

> however i feel this to be very misleading, as the specs do not show the
> order nor the fixed length of the parameter list.

If you have a fixed length and format, it strikes me that a list isn't the
data structure you want given that a list is by definition variable-length.
 Is there a reason you're not using a tuple instead of that list?  Something
like this?:

myfun({One, Two}) -> ...

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It's not been about our revenue or profit or whatnot."
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