Re: mathlib

[Enrico Colombini <erix@...>]

On 06/04/2014 17.09, Roberto Ierusalimschy wrote:
> Repeating ourselves: our suggestion involves moving sinh, cosh, and tanh
> from mathlib to the loadable mathx library (which already exists [1]), as
> we do not see (and nobody really addressed that specific point until
> now) them being more used/important/basic/whatever than several other
> functions there.

As I see it:

- pow() is a duplicate and should go.

- deg(), rad() could also go because it is slightly absurd to use a 
function in place of a multiplicative constant that can be trivially 
defined (I use deg2rad and rad2deg).

- I never used sinh/cosh/tanh() but I understand that they can be very 
useful in specialized fields. Moving them to mathx looks reasonable, but...

...but mathx is a C library; unfortunately (please correct me if I am 
wrong) there is no simple way for users to just get it from a binary 
distribution; they must use either a compiler or a library manager, both 
of which add significant complications to the use of a simple Lua 
executable.
(by the way, mathx is also not advertised on the official site)

Solve this and you will be able to remove even more functions from the 
core distribution without anybody complaining :-)

I think Lua has reached a stage where downloadable, ready-to-use 
libraries for major operating systems (matched to LuaBinaries-style 
executables) from a 'blessed' place could be of great help to people 
that are just using Lua as a tool and not embedding it.

In the meantime, I think it would probably be a good idea to leave 
sinh/cosh/tanh() where they are, because people currently using them 
with a plain Lua executable would have to do a nontrivial effort to add 
them back just to keep their programs working.

A compromise could be to add mathx to the standard distribution with a 
compilation switch in luaconf.h to include it, but that would be a very 
slippery road (besides, mathx is C99).

--
  Enrico