Task #11474

* filter.c (filter_equal): Takes two filters instead of one.
(lfilt_k, rfilt_k): New keyword variables.
(filter_init): New keyword variables initialized.

* filter.h (filter_equal): Declaration updated.
(lfilt_k, rfilt_k): Declared.

* lib.c (funcall4): New function.
(do_curry_1234_34): New static function.
(curry_1234_34): New function.
(do_swap_12_21): New static function.
(swap_12_21): New function.

* lib.h (funcall4, curry_1234_34, swap_12_21): Declared.

* match.c (dest_bind): Swap use the function argument swapping
combinator when calling tree find such that the value
being searched is on the left and pattern material is on the right.
(v_bind): Implemented :lfilt and :rfilt.

* txr.1: Documented :lfilt and :rfilt.

1 files changed, 36 insertions, 0 deletions

diff --git a/lib.c b/lib.c
index 98a9a056..064cb8ee 100644
--- a/lib.c
+++ b/lib.c
@@ -1541,6 +1541,22 @@ val funcall3(val fun, val arg1, val arg2, val arg3)
   }
 }
 
+val funcall4(val fun, val arg1, val arg2, val arg3, val arg4)
+{
+  type_check(fun, FUN);
+
+  switch (fun->f.functype) {
+  case F4:
+    return fun->f.f.f4(fun->f.env, arg1, arg2, arg3, arg4);
+  case N4:
+    return fun->f.f.n4(arg1, arg2, arg3, arg4);
+  default:
+    uw_throwf(error_s, lit("funcall4: wrong number of arguments"));
+  }
+}
+
+
+
 
 val reduce_left(val fun, val list, val init, val key)
 {
@@ -1593,6 +1609,16 @@ val curry_123_23(val fun3, val arg1)
   return func_f2(cons(fun3, arg1), do_curry_123_23);
 }
 
+static val do_curry_1234_34(val fcons, val arg3, val arg4)
+{
+  return funcall4(car(fcons), car(cdr(fcons)), cdr(cdr(fcons)), arg3, arg4);
+}
+
+val curry_1234_34(val fun4, val arg1, val arg2)
+{
+  return func_f2(cons(fun4, cons(arg1, arg2)), do_curry_1234_34);
+}
+
 static val do_chain(val fun1_list, val arg)
 {
   for (; fun1_list; fun1_list = cdr(fun1_list))
@@ -1648,6 +1674,16 @@ val andf(val first_fun, ...)
   return func_f1(out, do_and);
 }
 
+static val do_swap_12_21(val fun, val left, val right)
+{
+  return funcall2(fun, right, left);
+}
+
+val swap_12_21(val fun)
+{
+  return func_f2(fun, do_swap_12_21);
+}
+
 val vector(val alloc)
 {
   cnum alloc_plus = c_num(alloc) + 2;