- From the left side of the derivation to the right becomes the derivation , from the right to the left becomes the statute
- LL's analysis is a continuous extension to the right process, similar to a loop, suitable for EBNF description. So ll is a pre-order traversal of the syntax tree, which is from top to bottom, from the beginning of the root node to the terminator of the leaf node terminator
- The shift-reduce process of LR is a recursive-regression process, and SR always starts with Terminator, terminating the Terminator as a non-terminator on the left side of the derivation. This is a sequential traversal of the syntax tree, which is from the low to the top, that is, from the leaf node of terminator to the root node of the starting non-terminator. Therefore, it is more appropriate to use the recursive BNF description. Since the left statute is equivalent to right derivation, it is called LR
Regular Language:
- Chomsky Norm Form Context-free
- Context-sensitive Grammar:
Classification of compiling principle languages
