[geary/wip/713891-traversable: 3/12] Adding some more methods I know we'll need

[Charles Lindsay <clindsay src gnome org>]

commit 05fe09715b44617e7fddd3933fbeff9726368e54
Author: Charles Lindsay <chaz yorba org>
Date:   Wed Dec 11 16:56:27 2013 -0800

    Adding some more methods I know we'll need

 src/engine/util/util-traversable.vala |   30 ++++++++++++++++++++++++++++++
 1 files changed, 30 insertions(+), 0 deletions(-)
---
diff --git a/src/engine/util/util-traversable.vala b/src/engine/util/util-traversable.vala
index b4889ff..3d5be23 100644
--- a/src/engine/util/util-traversable.vala
+++ b/src/engine/util/util-traversable.vala
@@ -60,6 +60,36 @@ public class Iterable<G> : BaseObject {
             .map<A>(x => { return (A) x; }));
     }
     
+    public G? first() {
+        if (!i.next())
+            return null;
+        return i.get();
+    }
+    
+    public G? first_matching(owned Gee.Predicate<G> f) {
+        foreach (G g in this) {
+            if (f(g))
+                return g;
+        }
+        return null;
+    }
+    
+    public bool any(owned Gee.Predicate<G> f) {
+        foreach (G g in this) {
+            if (f(g))
+                return true;
+        }
+        return false;
+    }
+    
+    public bool all(owned Gee.Predicate<G> f) {
+        foreach (G g in this) {
+            if (!f(g))
+                return false;
+        }
+        return true;
+    }
+    
     public Collection<G> to_collection(owned Gee.EqualDataFunc<G>? equal_func = null) {
         return new Collection<G>(i, equal_func);
     }