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| o An introductory chapter describing what a compiler is. | * An introductory chapter describing what a compiler is. * A chapter or two on syntax equations, using Backus-Naur Form (BNF). |
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| o A chapter or two on syntax equations, using Backus-Naur Form (BNF). o A chapter or two on lexical scanning, with emphasis on |
* A chapter or two on lexical scanning, with emphasis on |
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| o Several chapters on parsing theory, beginning with top-down | * Several chapters on parsing theory, beginning with top-down |
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| o A chapter on intermediate languages, with emphasis on P-code | * A chapter on intermediate languages, with emphasis on P-code |
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| o Many chapters on alternative ways to handle subroutines and | * Many chapters on alternative ways to handle subroutines and |
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| o A chapter toward the end on code generation, usually for some | * A chapter toward the end on code generation, usually for some |
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| o A final chapter or two on optimization. This chapter often | * A final chapter or two on optimization. This chapter often |
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| * 所有的Identifier用single character来代替，不考虑空格（即词法规定不允许用户写空格） | * 所有的Identifier用single character来代替，不考虑空格（即词法规定不允许用户写空格）。作者认为如果他能正确处理I-T-L，那么他也能让IF-THEN-ELSE工作 * 只处理实时I/O，不处理File I/O。 * 忽略error correction/recovery。遇到第一个error即停机，但这不是崩溃。 |
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| 1. 从源代码直接生成汇编代码。不需要中间码 1. 延后对module的构建，直至真的需要它的时候 * 把每一个将来可能会用上的功能都提前封装是一个疯狂的做法，几乎肯定是错误的 * 尽量使用现有的module，除非你真的需要一个更强大的一点的，即便如此，也仅仅把注意力集中到该module上 1. 不纠缠于P-code等中间码或者想象的CPUs等，从第一天开始做出来的东西就要是可以工作的，即便它不完善 |
申明不会采用典型教科书上关于编译器的教学顺序，比如：
- An introductory chapter describing what a compiler is.
- A chapter or two on syntax equations, using Backus-Naur Form (BNF).
- A chapter or two on lexical scanning, with emphasis on
- deterministic and non-deterministic finite automata.
- Several chapters on parsing theory, beginning with top-down
- recursive descent, and ending with LALR parsers.
- A chapter on intermediate languages, with emphasis on P-code
- and similar reverse polish representations.
- Many chapters on alternative ways to handle subroutines and
- parameter passing, type declarations, and such.
- A chapter toward the end on code generation, usually for some
- imaginary CPU with a simple instruction set. Most readers (and in fact, most college classes) never make it this far.
- A final chapter or two on optimization. This chapter often
- goes unread, too.
作者不会遵照这些，而是带着你直接上手写一个能工作的编译器，采用他的方式：
- KISS原则
- 所有的Identifier用single character来代替，不考虑空格（即词法规定不允许用户写空格）。作者认为如果他能正确处理I-T-L，那么他也能让IF-THEN-ELSE工作
- 只处理实时I/O，不处理File I/O。
- 忽略error correction/recovery。遇到第一个error即停机，但这不是崩溃。
- 只讨论一种情形的解析：top-down、recursive descent parsing
- 自顶向下、递归下降的情形，作者认为这是唯一一种支持手写编译器的技术选型
- 从源代码直接生成汇编代码。不需要中间码
- 延后对module的构建，直至真的需要它的时候
- 把每一个将来可能会用上的功能都提前封装是一个疯狂的做法，几乎肯定是错误的
- 尽量使用现有的module，除非你真的需要一个更强大的一点的，即便如此，也仅仅把注意力集中到该module上
- 不纠缠于P-code等中间码或者想象的CPUs等，从第一天开始做出来的东西就要是可以工作的，即便它不完善