1 files changed, 49 insertions, 3 deletions

diff --git a/main/filter.go b/main/filter.go
index 95e6d82..662fa7b 100644
--- a/main/filter.go
+++ b/main/filter.go
@@ -3,10 +3,10 @@ package main
 type PathFilter struct {
 	initial PathFilterState
 }
-func (filter PathFilter) exec(state *ProgramState) bool {
+func (filter PathFilter) exec(space WalkItem) bool {
 	pathFilterState := make(map[PathFilterState]struct{})
 	pathFilterState[filter.initial] = struct{}{}
-	for _, segment := range state.space.path {
+	for _, segment := range space.path {
 		nextPathFilterState := make(map[PathFilterState]struct{})
 		for curState := range pathFilterState {
 			for nextState := range curState.eat(segment) {
@@ -23,12 +23,58 @@ func (filter PathFilter) exec(state *ProgramState) bool {
 	return false
 }
 
+type MapTerminalFilter struct {}
+func (filter MapTerminalFilter) exec(space WalkItem) bool {
+	terminal, isTerminal := space.value.(TerminalValue)
+	if !isTerminal {
+		return false
+	}
+	return terminal == MapBegin || terminal == MapEnd
+}
+
+type NonTerminalFilter struct {}
+func (filter NonTerminalFilter) exec(space WalkItem) bool {
+	_, isTerminal := space.value.(TerminalValue)
+	return !isTerminal
+}
+
 type RangeFilter struct {
 	start Filter
 	end Filter
 	active bool
 }
+func (filter *RangeFilter) exec(space WalkItem) bool {
+	if filter.active {
+		if filter.end.exec(space) {
+			filter.active = false
+		}
+		return true
+	} else {
+		if filter.start.exec(space) {
+			filter.active = true
+		}
+		return filter.active
+	}
+}
+
+type BeginTerminalFilter struct {}
+func (filter BeginTerminalFilter) exec(space WalkItem) bool {
+	terminal, isTerminal := space.value.(TerminalValue)
+	if !isTerminal {
+		return false
+	}
+	return terminal == ArrayBegin || terminal == MapBegin
+}
+
+type EndTerminalFilter struct {}
+func (filter EndTerminalFilter) exec(space WalkItem) bool {
+	terminal, isTerminal := space.value.(TerminalValue)
+	if !isTerminal {
+		return false
+	}
+	return terminal == ArrayEnd || terminal == MapEnd
+}
 
 type Filter interface {
-	exec(*ProgramState) bool
+	exec(WalkItem) bool
 }
\ No newline at end of file