1 files changed, 64 insertions, 0 deletions
diff --git a/examples/manual/expr.y b/examples/manual/expr.y
new file mode 100644
index 0000000..1ac3092
--- /dev/null
+++ b/examples/manual/expr.y
@@ -0,0 +1,64 @@
+/*
+ * expr.y : A simple yacc expression parser
+ *          Based on the Bison manual example. 
+ */
+
+%{
+#include <stdio.h>
+#include <math.h>
+
+%}
+
+%union {
+   float val;
+}
+
+%token NUMBER
+%token PLUS MINUS MULT DIV EXPON
+%token EOL
+%token LB RB
+
+%left  MINUS PLUS
+%left  MULT DIV
+%right EXPON
+
+%type  <val> exp NUMBER
+
+%%
+input   :
+        | input line
+        ;
+
+line    : EOL
+        | exp EOL { printf("%g\n",$1);}
+
+exp     : NUMBER                 { $$ = $1;        }
+        | exp PLUS  exp          { $$ = $1 + $3;   }
+        | exp MINUS exp          { $$ = $1 - $3;   }
+        | exp MULT  exp          { $$ = $1 * $3;   }
+        | exp DIV   exp          { $$ = $1 / $3;   }
+        | MINUS  exp %prec MINUS { $$ = -$2;       }
+        | exp EXPON exp          { $$ = pow($1,$3);}
+        | LB exp RB                      { $$ = $2;        }
+        ;
+
+%%
+
+yyerror(char *message)
+{
+  printf("%s\n",message);
+}
+
+int main(int argc, char *argv[])
+{
+  yyparse();
+  return(0);
+}
+
+
+
+
+
+
+
+