signal: Add signal-call.

* sly/signal.scm (signal-call): New procedure.
* doc/api/signals.texi: Add docs.

2 files changed, 13 insertions, 1 deletions

diff --git a/doc/api/signals.texi b/doc/api/signals.texi
index 0d8c589..f2773d2 100644
--- a/doc/api/signals.texi
+++ b/doc/api/signals.texi
@@ -218,3 +218,8 @@ the coroutine defined by @var{body}.  A special @code{yield} syntax is
 available within @var{body} to specify which values are passed to the
 signal.
 @end deffn
+
+@deffn {Scheme Procedure} signal-call @var{proc-signal} . @var{arg-signals}
+Create a new signal that applies the procedure within
+@var{proc-signal} to the arguments in @var{arg-signals}.
+@end deffn
diff --git a/sly/signal.scm b/sly/signal.scm
index 0ddda2a..e57e880 100644
--- a/sly/signal.scm
+++ b/sly/signal.scm
@@ -53,7 +53,8 @@
             signal-every signal-timer signal-since
             signal-delay
             signal-throttle
-            signal-generator))
+            signal-generator
+            signal-call))
 
 ;;;
 ;;; Signals
@@ -425,3 +426,9 @@ ticks."
         (lambda () body ...))
       handler))
     signal))
+
+(define (signal-call proc-signal . arg-signals)
+  "Create a new signal that applies the procedure within PROC-SIGNAL
+to the arguments in ARG-SIGNALS."
+  (apply signal-map (lambda (proc . args) (apply proc args))
+         proc-signal arg-signals))