编译原理中，算符优先文法和LR(1)文法啥关系
它是LR(1)的子集
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我在stackoverflow问了下，这是回答。说的比较深奥，因为我还没搞明白算符优先文法，所以这个回答里说的有些特点什么的看不太懂。把原文贴上，不翻译了。大家参考下。
【编译原理中，算符优先文法和LR(1)文法啥关系】 An operator grammar is a context-free grammar in which there are no consecutive non-terminals in any right-hand side. (Intuitively, every production has an operator, as in the grammar for mathematical expressions.)
A operator precedence grammar is an operator grammar in which the parsing automaton can decide whether to shift or reduce based simply on a precedence relationship between the terminal closest to the top of the parsing stack and the lookahead token. Such a precedence relation does not need to be complete, nor transitive, nor antisymmetric.
I\u0026#39;m pretty sure that every operator precedence grammar is LR(1), but the converse is certainly not true. An LR(1) grammar does not have the restriction against consecutive non-terminals, for example, and it is quite possible for the shift/reduce decision in an LR(1) grammar to not be correlated with the uppermost terminal in the parse stack and the lookahead token. Nonetheless, some useful languages can be expressed with an operator precedence grammar.
Like LR-parsing, operator-precedence parsing is a bottom-up technique. It is possibly easier to understand than the LALR algorithm, but it has no other obvious advantage: it is not faster; it is less reliable (in the sense that some implementations will recognize erroneous sentences); and it is harder to verify. Before the LALR algorithm was discovered, however, the size of LR(1) automata (and the limited computing resources available) made operator-precedence parsing seem like a reasonable approach.
These days, you would be much better off using one of the many available parser generators.
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