tweaks to filter and regex handling to allow for continuous usage of …

…Filter object

filter.cpp

@@ -1028,16 +1028,9 @@ void Filter::parse(const char* exp, bool debug)
             }    
         }
 
-        if (tree!=NULL)
-        {
-            delete tree;
-            tree = NULL;
-        }
-        else
-        {
-            tree = new Node();
-            parse(exp_no_space.c_str(), exp_no_space.size(), tree, debug);
-        }
+        reset();
+        tree = new Node();
+        parse(exp_no_space.c_str(), exp_no_space.size(), tree, debug);
 
         if (!tree->type&VT_BOOL)
         {
@@ -1079,6 +1072,25 @@ bool Filter::apply(bcf_hdr_t *h, bcf1_t *v, Variant *variant, bool debug) //recu
     }
 }
 
+/**
+ * Attempts to simplify the expression tree by collapsing nodes that can be precomputed.
+ */
+void Filter::simplify()
+{
+}
+
+/**
+ * Resets filter.
+ */
+void Filter::reset()
+{
+    if (tree!=NULL)
+    {
+        delete tree;
+        tree = NULL;
+    }
+}
+
 /**
  * Constructs the expression tree.
  */

filter.h

@@ -160,6 +160,11 @@ class Filter
      * Attempts to simplify the expression tree by collapsing nodes that can be precomputed.
      */
     void simplify();
+
+    /**
+     * Resets filter.
+     */
+    void reset();
 
     private:
 

pregex.h

@@ -32,6 +32,18 @@
 /**
  * Class for PERL regular expressions.
  * Wrapper for pcre2.
+ *
+ * Usage
+ *
+ * //using C++ strings
+ * std::string regex = "abc";
+ * pregex.set(regex);
+ * std::string target = "aabcc";
+ * bool b = pregex.match(target);
+ *
+ * //using C strings
+ * pregex.set(regex.s);
+ * bool b = pregex.match(target.s);
  */
 class PERLregex
 {
@@ -69,7 +81,7 @@ class PERLregex
      * Destructor.
      */
     ~PERLregex();
-    
+
     /**
      * Sets the regular expression amd compiles it for matching later.
      */
@@ -79,16 +91,16 @@ class PERLregex
      * Sets the regular expression amd compiles it for matching later.
      */
     void set(char* regex);
-        
+
     /**
      * Matches a text against a regular expression that has been compiled in set().
      */
     bool match(std::string& text);
-        
+
     /**
      * Matches a text against a regular expression that has been compiled in set().
      */
-    bool match(char* text);    
+    bool match(char* text);
 };
 
 #endif