define-record-type*: Add `letrec*' behavior.

* guix/utils.scm (define-record-type*)[make-syntactic-constructor]: Bind
  all the ((FIELD VALUE) ...) in a `letrec*'.  Adjust `field-value'
  accordingly.

* tests/utils.scm ("define-record-type* with letrec* behavior"): New
  test.

1 files changed, 16 insertions, 0 deletions

diff --git a/tests/utils.scm b/tests/utils.scm
index 83a78b7a78..4a24e23df9 100644
--- a/tests/utils.scm
+++ b/tests/utils.scm
@@ -112,6 +112,22 @@
          (match (foo (bar 1))
            (($ <foo> 1 42) #t)))))
 
+(test-assert "define-record-type* with letrec* behavior"
+  ;; Make sure field initializers can refer to each other as if they were in
+  ;; a `letrec*'.
+  (begin
+    (define-record-type* <bar> bar make-bar
+      foo?
+      (x bar-x)
+      (y bar-y (default (+ 40 2)))
+      (z bar-z))
+    (and (match (bar (x 1) (y (+ x 1)) (z (* y 2)))
+           (($ <bar> 1 2 4) #t))
+         (match (bar (x 7) (z (* x 3)))
+           (($ <bar> 7 42 21)))
+         (match (bar (z 21) (x (/ z 3)))
+           (($ <bar> 7 42 21))))))
+
 (test-end)