trivial commit

.gitignore

@@ -1 +1,9 @@
 *.s
+assignments/PA2/cgen
+assignments/PA2/cool-lex.cc
+assignments/PA2/parser
+assignments/PA2/semant
+assignments/PA2/lexer
+*.o
+.cache/
+compile_commands.json

CS143体验报告.md

@@ -32,3 +32,13 @@
 - 它的 `case` 也是奇葩，居然是用来做动态类型匹配的，匹配的是类型而不是值，和正常的 `switch-case` 完全不一样，倒是有点像 `rust` 里面的那种感觉。
 
 测试的话，虽然 handout 里面说是直接 `make test` 然后对比输出，不过我也没看到它哪里有所谓的 reference implementation，自己看了看测例觉着没啥问题就行了。
+
+### PA2
+
+PA 2-5 正式写编译器。PA2 写词法分析器，首先读一遍 README 和 handout。
+
+> 环境配置
+> 因为这个项目的结构非常的智障，导致需要进行一些配置才能让 `clangd` 正常工作。因为是 `Makefile` 项目，所以不能直接生成 `compile_commands.json`。
+> 1. 安装 `apt install bear`，这个工具可以拦截 `make` 命令来生成上述的文件。
+> 2. 在 PA2 目录下，运行 `make clean && bear -- make lexer`，然后 `clangd` 应该就不会找不到头文件之类的了
+

assignments/PA2/cool-lex.d

@@ -1,5 +1,5 @@
 cool-lex.o cool-lex.d : cool-lex.cc ../../include/PA2/cool-parse.h \
-  ../../include/PA2/copyright.h ../../include/PA2/cool-io.h \
+ ../../include/PA2/copyright.h ../../include/PA2/cool-io.h \
-  ../../include/PA2/tree.h ../../include/PA2/stringtab.h \
+ ../../include/PA2/tree.h ../../include/PA2/stringtab.h \
-  ../../include/PA2/list.h ../../include/PA2/stringtab.h \
+ ../../include/PA2/list.h ../../include/PA2/stringtab.h \
-  ../../include/PA2/utilities.h
+ ../../include/PA2/utilities.h

assignments/PA2/cool.flex

@@ -1,3 +1,4 @@
+%{
 /*
  *  The scanner definition for COOL.
  */
@@ -7,7 +8,6 @@
  *  output, so headers and global definitions are placed here to be visible
  * to the code in the file.  Don't remove anything that was here initially
  */
-%{
 #include <cool-parse.h>
 #include <stringtab.h>
 #include <utilities.h>
@@ -50,6 +50,33 @@ extern YYSTYPE cool_yylval;
  */
 
 DARROW          =>
+DIGIT           [0-9] 
+DIGITS          {DIGIT}+
+/*  */
+/* Keywords Definition*/
+/* Except for the constants true and false, keywords are case insensitive */
+K_CLASS         (?i:class)
+K_ELSE          (?i:else)
+K_FI            (?i:fi)
+K_IF            (?i:if)
+K_IN            (?i:in)
+K_INHERITS      (?i:inherits)
+K_ISVOID        (?i:isvoid)
+K_LET           (?i:let)
+K_LOOP          (?i:loop)
+K_POOL          (?i:pool)
+K_THEN          (?i:then)
+K_WHILE         (?i:while)
+K_CASE          (?i:case)
+K_ESAC          (?i:esac)
+K_NEW           (?i:new)
+K_OF            (?i:of)
+K_NOT           (?i:not)
+/* the first letter of true/false must be lowercase; the trailing may be upper or lower case. */
+K_TRUE          t(?i:rue)
+K_FALSE         f(?i:alse)
+
+
 
 %%