Merge branch 'master' of https://github.com/VictorRodriguez/compilers-lecture

Author: VictorRodriguez

labs/04/calculator_v2_linux_zoo/Makefile

@@ -0,0 +1,11 @@
+all:
+  yacc -d simplecalc.y
+  lex simplecalc.l
+  gcc y.tab.c lex.yy.c -o simplecalc
+
+clean:
+  rm -rf simplecalc
+  rm -rf lex.yy.c
+  rm -rf y.tab.c
+  rm -rf y.tab.h
+  rm -rf y.tab.h.gch

labs/04/calculator_v2_linux_zoo/simplecalc.l

@@ -0,0 +1,16 @@
+%{
+#include "y.tab.h"
+extern int yylval;
+
+%}
+
+%option noyywrap
+
+
+%%
+[0-9]+                          { yylval = atoi(yytext); return NUMBER; }
+[a-z]                           { yylval = yytext[0]; return NAME; }
+[ \t] ;                         /* ignore whitespace */
+\n return 0;            /* logical EOF */
+. return yytext[0];
+%%

labs/04/calculator_v2_linux_zoo/simplecalc.y

@@ -0,0 +1,28 @@
+%{
+#include <stdio.h>
+int yylex();
+ void yyerror (char const *s) {
+   fprintf (stderr, "%s\n", s);
+ }
+%}
+
+
+%token NAME NUMBER
+%%
+
+statement: NAME '=' expression          {printf("%c = %d\n", $1,$3);}
+ | expression                                           {printf("= %d\n", $1);}
+ ;
+expression: expression '+' NUMBER   { $$ = $1 + $3;}
+ | expression '-' NUMBER            { $$ = $1 - $3;}
+ | expression '*' NUMBER            { $$ = $1 * $3;}
+ | '(' expression ')'                           {$$ = $2;}
+ | NUMBER                           {$$ = $1;}
+ ;
+
+%%
+
+int main(){
+        yyparse();
+        return 0;
+}

labs/04/lex_examples/example3_linuxzoo.l

@@ -0,0 +1,21 @@
+%{
+#include <stdio.h>
+%}
+
+%option noyywrap
+
+%%
+[a-zA-Z][a-zA-Z0-9]*    { printf("WORD "); }
+[a-zA-Z0-9\/.-]+        { printf("FILENAME "); }
+\"                      { printf("QUOTE "); }
+\{                      { printf("OBRACE "); }
+\}                      { printf("EBRACE "); }
+;                       { printf("SEMICOLON "); }
+\n                      { printf("\n"); }
+[ \t]+                  /* ignore whitespace */
+%%
+
+int main() {
+    yylex();
+    return 0;
+}