From 56bb28dfc6058e611f763695ee759989237cbb55 Mon Sep 17 00:00:00 2001
From: Ryan Culpepper <ryanc@racket-lang.org>
Date: Wed, 11 May 2011 00:45:30 -0600
Subject: [PATCH] unstable/syntax: added explode-module-path-index

---
 collects/unstable/scribblings/syntax.scrbl | 14 ++++++++++++++
 collects/unstable/syntax.rkt               | 14 ++++++++++++--
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/collects/unstable/scribblings/syntax.scrbl b/collects/unstable/scribblings/syntax.scrbl
index 6747eb2b49..2fcab2e2ec 100644
--- a/collects/unstable/scribblings/syntax.scrbl
+++ b/collects/unstable/scribblings/syntax.scrbl
@@ -18,6 +18,20 @@
 
 @unstable[@author+email["Ryan Culpepper" "ryanc@racket-lang.org"]]
 
+@defproc[(explode-module-path-index [mpi module-path-index?])
+         (listof (or/c module-path? resolved-module-path? #f))]{
+
+Unfolds @racket[mpi] using @racket[module-path-index-split], returning
+a list of the relative module paths together with the terminal
+resolved module path or @racket[#f] for the ``self'' module.
+
+@examples[#:eval the-eval
+(explode-module-path-index (car (identifier-binding #'lambda)))
+(explode-module-path-index (caddr (identifier-binding #'lambda)))
+(explode-module-path-index (car (identifier-binding #'define-values)))
+]
+}
+
 @;{----}
 
 @margin-note{This binding was added by Vincent St-Amour.}
diff --git a/collects/unstable/syntax.rkt b/collects/unstable/syntax.rkt
index c34bbbb18b..44d9810efa 100644
--- a/collects/unstable/syntax.rkt
+++ b/collects/unstable/syntax.rkt
@@ -7,13 +7,14 @@
          syntax-list
 
          ;; by cce:
-
          syntax-source-file-name
          syntax-source-directory
 
          ;; by stamourv:
+         format-unique-id
 
-         format-unique-id)
+         ;; by ryanc
+         explode-module-path-index)
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;;
@@ -60,3 +61,12 @@
   ((make-syntax-introducer) (apply format-id
                                    lctx #:source src #:props props #:cert cert
                                    fmt args)))
+
+;; by ryanc
+
+(define (explode-module-path-index mpi)
+  (let-values ([(x y) (module-path-index-split mpi)])
+    (cons x
+          (if (module-path-index? y)
+              (explode-module-path-index y)
+              (list y)))))