Second argument optional in trunc.

* arith.c (trunc1): New static function.
(trunc): Detect a missing second argument and call func1.

* eval.c (eval_init): Update registration of trunc
intrinsic to make second arg optional.

* txr.1: Describe optional argument of trunc. Trunc documentation
is merged with the floor, ceil and round section.
The mod and trunc-rem functions are split off into their own
sections, leaving the / function described by itself.
The documentation of / is substantially revised.

1 files changed, 1 insertions, 1 deletions

diff --git a/eval.c b/eval.c
index 0312292a..bc58d303 100644
--- a/eval.c
+++ b/eval.c
@@ -5691,7 +5691,7 @@ void eval_init(void)
   reg_fun(intern(lit("-"), user_package), func_n1v(minusv));
   reg_fun(intern(lit("*"), user_package), func_n0v(mulv));
   reg_fun(intern(lit("abs"), user_package), func_n1(abso));
-  reg_fun(intern(lit("trunc"), user_package), func_n2(trunc));
+  reg_fun(intern(lit("trunc"), user_package), func_n2o(trunc, 1));
   reg_fun(intern(lit("mod"), user_package), func_n2(mod));
   reg_fun(intern(lit("trunc-rem"), user_package), func_n2(trunc_rem));
   reg_fun(intern(lit("wrap"), user_package), func_n3(wrap));