scannersyn

/* Code: */
#include <stdio.h>
#include <stdlib.h>
/* A couple of globals */
int lineno = 0;
int number;
char string[100];
#define NUMBER 1
#define STRING 2
#define ASSIGN 3
#define DIV 4

int main(int argc, char **argv){
  int rc;
  while ((rc=yylex())){
    switch (rc){
    case NUMBER:
      printf("We recognized a number of value %d\n", number);
      break;
    case STRING:
      printf("We recognized a string of value %s\n", string);
      break;
    case '+':
      printf ("+\n");
      break;

    }
  }
  return 0;
}

int yylex(){
  int c;
  while ((c=getchar()) == ' ' || c == '\t')
    ;                      /* Do nothing */

  if (c == EOF)
    return 0;

  if (isdigit(c)){
    ungetc(c,stdin);
    scanf("%d", &number);
    return NUMBER;
  } else if (c=='+'||c=='-'||c=='/'||c=='*'||c=='('||c==')'){
    return c;
  } else if (c==':'){
      c=getchar();
      if (c=='=')
        return ASSIGN;
  } else if (c=='/'){
      c=getchar();
      if (c=='*'||c=='/')
        c=getchar();
        if (c=='*/'||'newline');
          return 0;
        else
          return DIV;
  } else {
    ungetc(c,stdin);
    scanf("%s", string);
    return STRING;
  }

}
/* scanner-simplest.c ends here */

/* make ./scanner-simplest in the directory
add new assignments to scanner-lex.c */