[erlang-questions] is_integer should always be used?

Dominic Williams <>
Fri Jul 4 00:11:36 CEST 2008


not norwegian swede a écrit :

> when programming erlang, should i always use is_integer
> if a float will make the function crash?

I think not. I think guards should not be used for type
checking, but used to write different clauses, when you want
to handle floats and ints differently.

Of course, I use test-driven programming, so I don't need
type checking for correctness. And the tests I write are
better at expressing how I intend the function to be used
than a mere guard. And adding a guard for optimisation's
sake would be premature, without profiling.

So, as a general rule, I let it crash, I don't use a guard.

> i havent used so much exception-prevention in erlang and
> it seems the language needs a lot of extra code stuck it
> in ebcause of this.

You must not be coding in Erlang the same way as I. I have
never had as little exception-handling code as when I code 
in Erlang.

Regards,

Dominic Williams
http://dominicwilliams.net



More information about the erlang-questions mailing list