Seonglae ChoR means rightmost derivation in reverse
Task in LR parsing: determining the handle, thus the next RSF
LR(0) means no need to look ahead to determine the handle
Item: a state representing the status of RHS recognition
- use a dot “.” to separate the recognized part and the rest
item
a state representing the status of RHS recognition
initial items
complete items
handle candidates
Action: shift or reduce (using which rule) based on state
table header is
- State
- Action
- shift
- accept
- reduce
- Rule if action is reduce
LR(0) Conflicts
Action (shift/reduce) at a state is unclear
- Shift-reduce conflict : one item can shift, another can reduce
- Reduce-reduce conflict : two (or more) items that can reduce
If no state has conflicts, the grammar is LR(0) grammar