high: Add memoized implementation procedure.

* drmaa/v1/high.scm (implementation): New procedure.

1 files changed, 9 insertions, 0 deletions

diff --git a/drmaa/v1/high.scm b/drmaa/v1/high.scm
index 8751da7..e0f4fbb 100644
--- a/drmaa/v1/high.scm
+++ b/drmaa/v1/high.scm
@@ -279,6 +279,15 @@
 (define (job-template . args)
   (apply make <job-template> args))
 
+(define implementation
+  (let ((result #false))
+    (lambda ()
+      "Return the DRMAA implementation.  This is a memoized procedure."
+      (or result
+          (begin
+            (set! result (low:get-drmaa-implementation))
+            result)))))
+
 (define-method (lower-job-template (instance <job-template>))
   (define klass (class-of instance))
   (define t (low:allocate-job-template!))