v0.0.96

rext/wrapper.go

@@ -29,6 +29,10 @@ type RegexMatchGroup struct {
 	end      int
 }
 
+type OptRegexMatchGroup struct {
+	v *RegexMatchGroup
+}
+
 func W(rex *regexp.Regexp) Regex {
 	return &regexWrapper{rex: rex, subnames: rex.SubexpNames()}
 }
@@ -97,7 +101,7 @@ func (m RegexMatch) GroupByIndex(idx int) RegexMatchGroup {
 	return RegexMatchGroup{haystack: m.haystack, start: m.submatchesIndex[idx*2], end: m.submatchesIndex[idx*2+1]}
 }
 
-// GroupByName returns the value of a matched group (group 0 == whole match)
+// GroupByName returns the value of a matched group (panics if not found!)
 func (m RegexMatch) GroupByName(name string) RegexMatchGroup {
 	for idx, subname := range m.subnames {
 		if subname == name {
@@ -107,6 +111,16 @@ func (m RegexMatch) GroupByName(name string) RegexMatchGroup {
 	panic("failed to find regex-group by name")
 }
 
+// GroupByName returns the value of a matched group (returns empty OptRegexMatchGroup if not found)
+func (m RegexMatch) GroupByNameOrEmpty(name string) OptRegexMatchGroup {
+	for idx, subname := range m.subnames {
+		if subname == name {
+			return OptRegexMatchGroup{&RegexMatchGroup{haystack: m.haystack, start: m.submatchesIndex[idx*2], end: m.submatchesIndex[idx*2+1]}}
+		}
+	}
+	return OptRegexMatchGroup{}
+}
+
 // ---------------------------------------------------------------------------------------------------------------------
 
 func (g RegexMatchGroup) Value() string {
@@ -128,3 +142,40 @@ func (g RegexMatchGroup) Range() (int, int) {
 func (g RegexMatchGroup) Length() int {
 	return g.end - g.start
 }
+
+// ---------------------------------------------------------------------------------------------------------------------
+
+func (g OptRegexMatchGroup) Value() string {
+	return g.v.Value()
+}
+
+func (g OptRegexMatchGroup) ValueOrEmpty() string {
+	if g.v == nil {
+		return ""
+	}
+	return g.v.Value()
+}
+
+func (g OptRegexMatchGroup) IsEmpty() bool {
+	return g.v == nil
+}
+
+func (g OptRegexMatchGroup) Exists() bool {
+	return g.v != nil
+}
+
+func (g OptRegexMatchGroup) Start() int {
+	return g.v.Start()
+}
+
+func (g OptRegexMatchGroup) End() int {
+	return g.v.End()
+}
+
+func (g OptRegexMatchGroup) Range() (int, int) {
+	return g.v.Range()
+}
+
+func (g OptRegexMatchGroup) Length() int {
+	return g.v.Length()
+}