diff options
Diffstat (limited to 'main/regexstate.go')
-rw-r--r-- | main/regexstate.go | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/main/regexstate.go b/main/regexstate.go new file mode 100644 index 0000000..16d5581 --- /dev/null +++ b/main/regexstate.go @@ -0,0 +1,48 @@ +package main + +type RegexState interface { + eat(char rune) []RegexState + accepting() bool +} + +type RegexNoneState struct {} +func (state RegexNoneState) eat(char rune) []RegexState { + return nil +} +func (state RegexNoneState) accepting() bool { + return true +} + +type RegexAnyState struct { + next RegexState +} +func (state RegexAnyState) eat(char rune) []RegexState { + return []RegexState{state.next} +} +func (state RegexAnyState) accepting() bool { + return false +} + +type RegexRuneState struct { + rune rune + next RegexState +} +func (state RegexRuneState) eat(char rune) []RegexState { + if char == state.rune { + return []RegexState{state.next} + } + return nil +} +func (state RegexRuneState) accepting() bool { + return false +} + +type RegexGroupState struct { + first, second RegexState +} +func (state RegexGroupState) eat(char rune) []RegexState { + return append(state.first.eat(char), state.second.eat(char)...) +} +func (state RegexGroupState) accepting() bool { + return state.first.accepting() || state.second.accepting() +} |