[erlang-questions] true

[Donald Steven]

I didn't know that about other functional languages.  As a retiree, I 
just program for fun and have done some in Haskell, whence I picked up 
'otherwise', which I much prefer.

On 3/30/2019 1:45 AM, Richard O'Keefe wrote:
> Just for the record, every functional programming
> language I know that *has* guards uses true just
> the way Erlang does. This actually goes back all
> the way to Lisp, where "if" had no "else".  You
> wrote (COND (g1 b1) ... (gn bn) (T be)), where T
> was (and remains) Lisp's version of 'true'.
> Clean and Haskell allow 'otherwise' as a synonym
> of 'True'.  I stick with 'True' because it is
> easier for me to understand.
>
> On Fri, 29 Mar 2019 at 03:16, <zxq9@REDACTED <mailto:zxq9@REDACTED>> 
> wrote:
>
>     On 2019年3月27日水曜日 18時21分36秒 JST Donald Steven wrote:
>     > As someone very new to Erlang, I find it interesting to follow the
>     > discussion on guards.
>     >
>     >
>     > FWIW, the *only* thing about Erlang that drives me to
>     distraction is the
>     > use of the atom 'true' as a reliable "or, if the above ain't so"
>     default
>     > value for the expression.  If only (how I wish it were so) the atom
>     > wasn't so often completely at odds -- and at times the inverse
>     -- of the
>     > normal English 'read' of the if expression.  Please consider
>     > grandfathering 'true' (not to break old code) and coming up with a
>     > logically less committed atom-of-the-future such as 'default' or
>     > 'otherwise'.
>
>     Use `case` and general matching instead of `if` and other boolean
>     constructs
>     and your life will be better.
>
>     In Erlang boolean comparison constructs apply mostly in *range*
>     comparisons,
>     not general comparisons. `if` means something *very* different in
>     Erlang
>     than you're used to.
>
>     -Craig
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