Match API improvements:

- Provide != operator and emptiness check method
- Provide empty match
- Improve const correctness

2 files changed, 23 insertions, 5 deletions

diff --git a/include/core/match.h b/include/core/match.h
index dcf10ae..4afbec7 100644
--- a/include/core/match.h
+++ b/include/core/match.h
@@ -49,10 +49,13 @@ class CompMatch {
 	CompMatch (const CompMatch &);
 	~CompMatch ();
 
+	static const CompMatch emptyMatch;
+
 	void update ();
 	bool evaluate (CompWindow *window);
 
-	CompString toString ();
+	CompString toString () const;
+	bool isEmpty () const;
 
 	CompMatch & operator= (const CompMatch &);
 	CompMatch & operator&= (const CompMatch &);
@@ -69,7 +72,8 @@ class CompMatch {
 	const CompMatch & operator& (const CompString &);
 	const CompMatch & operator| (const CompString &);
 
-	bool operator== (const CompMatch &);
+	bool operator== (const CompMatch &) const;
+	bool operator!= (const CompMatch &) const;
 
     private:
 	PrivateMatch *priv;
diff --git a/src/match.cpp b/src/match.cpp
index a16c44a..072083e 100644
--- a/src/match.cpp
+++ b/src/match.cpp
@@ -39,6 +39,8 @@
 #include "privatescreen.h"
 #include "privatewindow.h"
 
+const CompMatch CompMatch::emptyMatch;
+
 class CoreExp : public CompMatch::Expression {
     public:
 	virtual ~CoreExp () {};
@@ -609,7 +611,7 @@ CompMatch::update ()
     matchResetOps (priv->op.op);
     matchUpdateOps (priv->op.op);
 }
-	
+
 bool
 CompMatch::evaluate (CompWindow *window)
 {
@@ -617,11 +619,17 @@ CompMatch::evaluate (CompWindow *window)
 }
 
 CompString
-CompMatch::toString ()
+CompMatch::toString () const
 {
     return matchOpsToString (priv->op.op);
 }
 
+bool
+CompMatch::isEmpty () const
+{
+    return (*this == emptyMatch);
+}
+
 CompMatch &
 CompMatch::operator= (const CompMatch &match)
 {
@@ -712,7 +720,13 @@ CompMatch::operator| (const CompString &str)
 }
 
 bool
-CompMatch::operator== (const CompMatch &match)
+CompMatch::operator== (const CompMatch &match) const
 {
     return matchOpsEqual (priv->op.op, match.priv->op.op);
 }
+
+bool
+CompMatch::operator!= (const CompMatch &match) const
+{
+    return !(*this == match);
+}