From cba913c5217fd4071419279da81fd02599715b6a Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <e.dolstra@tudelft.nl>
Date: Tue, 17 Oct 2006 11:05:34 +0000
Subject: [PATCH] * dirOf: return a path if the argument is a path.

---
 src/libexpr/primops.cc | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/src/libexpr/primops.cc b/src/libexpr/primops.cc
index 536345f22..6b4858d80 100644
--- a/src/libexpr/primops.cc
+++ b/src/libexpr/primops.cc
@@ -316,11 +316,15 @@ static Expr primBaseNameOf(EvalState & state, const ATermVector & args)
 
 
 /* Return the directory of the given path, i.e., everything before the
-   last slash. */
+   last slash.  Return either a path or a string depending on the type
+   of the argument. */
 static Expr primDirOf(EvalState & state, const ATermVector & args)
 {
     PathSet context;
-    return makeStr(dirOf(coerceToPath(state, args[0], context)), context);
+    Expr e = evalExpr(state, args[0]); ATerm dummy;
+    bool isPath = matchPath(e, dummy);
+    Path dir = dirOf(coerceToPath(state, e, context));
+    return isPath ? makePath(toATerm(dir)) : makeStr(dir, context);
 }