moved phase-of-enclosing-module to unstable/syntax

closes PR 11970

collects/syntax/parse/private/litconv.rkt

@@ -7,7 +7,8 @@
                      "rep-data.rkt"
                      "rep.rkt"
                      "kws.rkt")
-         "runtime.rkt")
+         "runtime.rkt"
+         (only-in unstable/syntax phase-of-enclosing-module))
 (provide define-conventions
          define-literal-set
          literal-set->predicate

collects/syntax/parse/private/rep.rkt

@@ -2,7 +2,8 @@
 (require (for-template racket/base
                        racket/stxparam
                        "keywords.rkt"
-                       "runtime.rkt")
+                       "runtime.rkt"
+                       (only-in unstable/syntax phase-of-enclosing-module))
          racket/contract/base
          "minimatch.rkt"
          syntax/id-table

collects/syntax/parse/private/runtime.rkt

@@ -369,16 +369,3 @@
      ;; For now, let #%app handle it.
      (with-syntax ([((kw-part ...) ...) #'((kw kwarg) ...)])
        #'(proc kw-part ... ... extra-parg ... parg ...))]))
-
-;; ----
-
-(provide phase-of-enclosing-module)
-
-(define-syntax (phase-of-enclosing-module stx)
-  (syntax-case stx ()
-    [(poem)
-     (let ([phase-within-module (syntax-local-phase-level)])
-       #`(let ([phase-of-this-expression
-                (variable-reference->phase (#%variable-reference))])
-           (- phase-of-this-expression
-              #,(if (zero? phase-within-module) 0 1))))]))

collects/unstable/scribblings/syntax.scrbl

@@ -26,6 +26,25 @@ resolved module path or @racket[#f] for the ``self'' module.
 ]
 }
 
+@defform[(phase-of-enclosing-module)]{
+
+Returns the phase level of the module in which the form occurs (and
+for the instantiation of the module in which the form is
+executed). For example, if a module is required directly by the
+``main'' module (or the top level), its phase level is 0. If a module
+is required for-syntax by the ``main'' module (or the top level), its
+phase level is 1.
+
+@examples[#:eval the-eval
+(module helper racket
+  (require unstable/syntax)
+  (displayln (phase-of-enclosing-module)))
+(require 'helper)
+(require (for-meta 1 'helper))
+]
+}
+
+
 @;{----}
 
 @addition{@author+email["Vincent St-Amour" "stamourv@racket-lang.org"]}

collects/unstable/syntax.rkt

@@ -1,7 +1,8 @@
 #lang racket/base
 ;; owner: ryanc (and cce and stamourv, where noted)
 (require racket/syntax
-         syntax/stx)
+         syntax/stx
+         (for-syntax racket/base))
 
 (provide (rename-out [stx-map syntax-map])
          syntax-list
@@ -15,7 +16,8 @@
          syntax-within?
 
          ;; by ryanc
-         explode-module-path-index)
+         explode-module-path-index
+         phase-of-enclosing-module)
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;
@@ -82,3 +84,12 @@
           (if (module-path-index? y)
               (explode-module-path-index y)
               (list y)))))
+
+(define-syntax (phase-of-enclosing-module stx)
+  (syntax-case stx ()
+    [(poem)
+     (let ([phase-within-module (syntax-local-phase-level)])
+       #`(let ([phase-of-this-expression
+                (variable-reference->phase (#%variable-reference))])
+           (- phase-of-this-expression
+              #,(if (zero? phase-within-module) 0 1))))]))