TXR Lisp gets exception handling.

* eval.c (op_catch, expand_catch_clause,
expand_catch): New static functions.
(expand): Handle catch operator.
(eval_init): Added catch operator to op_table,
and registered new functions throw, throwf and error.

* txr.1: Documented catch operator and created
stub section for throw, throwf and error.

* txr.vim: Updated.

* unwind.c (uw_throwfv, uw_errorfv): New functions.

* unwind.h (uw_throwfv, uw_errorfv): Declared.

1 files changed, 16 insertions, 0 deletions

diff --git a/unwind.c b/unwind.c
index ac99665a..ac4bb79d 100644
--- a/unwind.c
+++ b/unwind.c
@@ -295,6 +295,14 @@ val uw_throwf(val sym, val fmt, ...)
   abort();
 }
 
+val uw_throwfv(val sym, val fmt, val args)
+{
+  val stream = make_string_output_stream();
+  (void) formatv(stream, fmt, args);
+  uw_throw(sym, get_string_from_stream(stream));
+  abort();
+}
+
 val uw_errorf(val fmt, ...)
 {
   va_list vl;
@@ -308,6 +316,14 @@ val uw_errorf(val fmt, ...)
   abort();
 }
 
+val uw_errorfv(val fmt, val args)
+{
+  val stream = make_string_output_stream();
+  (void) formatv(stream, fmt, args);
+  uw_throw(error_s, get_string_from_stream(stream));
+  abort();
+}
+
 val type_mismatch(val fmt, ...)
 {
   va_list vl;