generate a specific default inner constructor using the field types, in

addition to the Any-typed constructor we currently generate.

fixes #7071

NEWS.md

@@ -9,8 +9,9 @@ New language features
   * `Tuple`s (of `Integer`s, `Symbol`s, or `Bool`s) can now be used as type
     parameters ([#5164]).
 
-  * Default "inner" constructors now accept any arguments. Constructors that
-    look like `MyType(a, b) = new(a, b)` can and should be removed ([#4026]).
+  * An additional default "inner" constructor accepting any arguments is now
+    generated. Constructors that look like `MyType(a, b) = new(a, b)` do not
+    need to be added manually ([#4026], [#7071]).
 
   * Expanded array type hierarchy to include an abstract ``DenseArray`` for
     in-memory arrays with standard strided storage ([#987], [#2345],
@@ -360,6 +361,7 @@ Deprecated or removed
 [#4042]: https://github.com/JuliaLang/julia/issues/4042
 [#5164]: https://github.com/JuliaLang/julia/issues/5164
 [#4026]: https://github.com/JuliaLang/julia/issues/4026
+[#7071]: https://github.com/JuliaLang/julia/issues/7071
 [#4799]: https://github.com/JuliaLang/julia/issues/4799
 [#4862]: https://github.com/JuliaLang/julia/issues/4862
 [#4048]: https://github.com/JuliaLang/julia/issues/4048

src/julia-syntax.scm

@@ -715,11 +715,18 @@
       (map (lambda (x) (gensy)) field-names)
       field-names))
 
-(define (default-inner-ctor name field-names field-types)
+(define (default-inner-ctors name field-names field-types)
   (let ((field-names (safe-field-names field-names field-types)))
-    `(function (call ,name ,@field-names)
-	       (block
-		(call new ,@field-names)))))
+    (list
+     ;; definition with field types for all arguments
+     `(function (call ,name
+		      ,@(map make-decl field-names field-types))
+		(block
+		 (call new ,@field-names)))
+     ;; definition with Any for all arguments
+     `(function (call ,name ,@field-names)
+		(block
+		 (call new ,@field-names))))))
 
 (define (default-outer-ctor name field-names field-types params bounds)
   (let ((field-names (safe-field-names field-names field-types)))
@@ -810,7 +817,7 @@
 	  (field-names (map decl-var fields))
 	  (field-types (map decl-type fields))
 	  (defs2 (if (null? defs)
-		     (list (default-inner-ctor name field-names field-types))
+		     (default-inner-ctors name field-names field-types)
 		     defs)))
      (for-each (lambda (v)
 		 (if (not (symbol? v))