Several changes

Switch timerlist to a slice of pointers to timers
Go mod

go.mod

@@ -0,0 +1,3 @@
+module git.bullercodeworks.com/brian/go-timertxt
+
+go 1.17

sort.go

@@ -45,7 +45,7 @@ func (ts *timerlistSort) Swap(l, r int) {
 }
 
 func (ts *timerlistSort) Less(l, r int) bool {
-	return ts.by(&ts.timerlists[l], &ts.timerlists[r])
+	return ts.by(ts.timerlists[l], ts.timerlists[r])
 }
 
 func (timerlist *TimerList) sortBy(by func(t1, t2 *Timer) bool) *TimerList {

timer.go

@@ -88,7 +88,9 @@ func NewTimer() *Timer {
 // ParseTimer parses the input text string into a Timer struct
 func ParseTimer(text string) (*Timer, error) {
 	var err error
-	timer := Timer{}
+	timer := Timer{
+		AdditionalTags: make(map[string]string),
+	}
 	timer.Original = strings.Trim(text, "\t\n\r ")
 	originalParts := strings.Fields(timer.Original)
 
@@ -209,3 +211,12 @@ func (timer *Timer) HasProject(project string) bool {
 	}
 	return false
 }
+
+func (timer *Timer) HasTag(name string) bool {
+	_, ok := timer.AdditionalTags[name]
+	return ok
+}
+
+func (timer *Timer) GetTag(name string) string {
+	return timer.AdditionalTags[name]
+}

timerlist.go

@@ -12,18 +12,26 @@ import (
 
 // TimerList represents a list of timer.txt timer entries.
 // It is usually loasded from a whole timer.txt file.
-type TimerList []Timer
+type TimerList []*Timer
 
 // NewTimerList creates a new empty TimerList.
 func NewTimerList() *TimerList {
 	return &TimerList{}
 }
 
+func (timerlist *TimerList) Size() int {
+	return len([]*Timer(*timerlist))
+}
+
+func (timerlist *TimerList) GetTimerSlice() []*Timer {
+	return []*Timer(*timerlist)
+}
+
 func (timerlist *TimerList) GetMostRecentTimer() (*Timer, error) {
 	var found *Timer
 	var latest time.Time
 	for i := range *timerlist {
-		t := &([]Timer(*timerlist))[i]
+		t := ([]*Timer(*timerlist))[i]
 		if t.FinishDate.IsZero() {
 			if t.StartDate.After(latest) {
 				found = t
@@ -43,7 +51,7 @@ func (timerlist *TimerList) GetMostRecentTimer() (*Timer, error) {
 }
 
 func (timerlist *TimerList) GetTimersInRange(start, end time.Time) *TimerList {
-	fltr := func(t Timer) bool {
+	fltr := func(t *Timer) bool {
 		if t.StartDate.Before(end) && t.StartDate.After(start) {
 			return true
 		}
@@ -56,13 +64,13 @@ func (timerlist *TimerList) GetTimersInRange(start, end time.Time) *TimerList {
 }
 
 func (timerlist *TimerList) GetTimersWithContext(context string) *TimerList {
-	return timerlist.Filter(func(t Timer) bool {
+	return timerlist.Filter(func(t *Timer) bool {
 		return t.HasContext(context)
 	})
 }
 
 func (timerlist *TimerList) GetTimersWithProject(project string) *TimerList {
-	return timerlist.Filter(func(t Timer) bool {
+	return timerlist.Filter(func(t *Timer) bool {
 		return t.HasProject(project)
 	})
 }
@@ -95,17 +103,17 @@ func (timerlist *TimerList) AddTimer(timer *Timer) {
 		t.Id++
 	}
 	// Now prepend the timer to the slice
-	*timerlist = append(*timerlist, Timer{})
+	*timerlist = append(*timerlist, &Timer{})
 	copy((*timerlist)[1:], (*timerlist)[0:])
-	(*timerlist)[0] = *timer
+	(*timerlist)[0] = timer
 }
 
 // GetTimer returns the Timer with the given timer 'id' from the TimerList.
 // Returns an error if Timer could not be found.
 func (timerlist *TimerList) GetTimer(id int) (*Timer, error) {
 	for i := range *timerlist {
-		if ([]Timer(*timerlist))[i].Id == id {
+		if ([]*Timer(*timerlist))[i].Id == id {
-			return &([]Timer(*timerlist))[i], nil
+			return ([]*Timer(*timerlist))[i], nil
 		}
 	}
 	return nil, errors.New("timer not found")
@@ -167,7 +175,7 @@ func (timerlist *TimerList) ArchiveTimerToFile(timer Timer, filename string) err
 
 // Filter filters the current TimerList for the given predicate (a function that takes a timer as input and returns a
 // bool), and returns a new TimerList. The original TimerList is not modified.
-func (timerlist *TimerList) Filter(predicate func(Timer) bool) *TimerList {
+func (timerlist *TimerList) Filter(predicate func(*Timer) bool) *TimerList {
 	var newList TimerList
 	for _, t := range *timerlist {
 		if predicate(t) {
@@ -180,7 +188,7 @@ func (timerlist *TimerList) Filter(predicate func(Timer) bool) *TimerList {
 // LoadFromFile loads a TimerList from *os.File.
 // Note: This will clear the current TimerList and overwrite it's contents with whatever is in *os.File.
 func (timerlist *TimerList) LoadFromFile(file *os.File) error {
-	*timerlist = []Timer{} // Empty timerlist
+	*timerlist = []*Timer{} // Empty timerlist
 	timerId := 1
 	scanner := bufio.NewScanner(file)
 	for scanner.Scan() {
@@ -194,7 +202,7 @@ func (timerlist *TimerList) LoadFromFile(file *os.File) error {
 			return err
 		}
 		timer.Id = timerId
-		*timerlist = append(*timerlist, *timer)
+		*timerlist = append(*timerlist, timer)
 		timerId++
 	}
 	if err := scanner.Err(); err != nil {