New cached sorting functions.

These functions are useful when sorting a sequence
using an expensive keyfun.

* autoload.c (csort_set_entries, csort_instantiate):
New static functions.
(autlod_init): Register autoloading of csort module
via new functions.

* stdlib/csort.tl: New file.

* tests/012/sort.tl: csort functions included in tests.

* txr.1: Documented.

* stdlib/doc-syms.tl: Updated.

1 files changed, 17 insertions, 0 deletions

diff --git a/autoload.c b/autoload.c
index d384879a..b87d560a 100644
--- a/autoload.c
+++ b/autoload.c
@@ -955,6 +955,22 @@ static val load_args_instantiate(void)
   return nil;
 }
 
+static val csort_set_entries(val fun)
+{
+  val name[] = {
+    lit("csort"), lit("cnsort"), lit("cssort"), lit("csnsort"),
+    nil
+  };
+  autoload_set(al_fun, name, fun);
+  return nil;
+}
+
+static val csort_instantiate(void)
+{
+  load(scat2(stdlib_path, lit("csort")));
+  return nil;
+}
+
 val autoload_reg(val (*instantiate)(void),
                  val (*set_entries)(val))
 {
@@ -1024,6 +1040,7 @@ void autoload_init(void)
   autoload_reg(constfun_instantiate, constfun_set_entries);
   autoload_reg(expander_let_instantiate, expander_let_set_entries);
   autoload_reg(load_args_instantiate, load_args_set_entries);
+  autoload_reg(csort_instantiate, csort_set_entries);
 
   reg_fun(intern(lit("autoload-try-fun"), system_package), func_n1(autoload_try_fun));
 }